diff --git a/gennghttpxfun.py b/gennghttpxfun.py
index 3114137d..eb95026d 100755
--- a/gennghttpxfun.py
+++ b/gennghttpxfun.py
@@ -100,6 +100,7 @@ OPTIONS = [
     "tls-ticket-key-memcached-max-fail",
     "request-phase-file",
     "response-phase-file",
+    "accept-proxy-protocol",
     "conf",
 ]
 
diff --git a/src/shrpx.cc b/src/shrpx.cc
index 9aac0cde..fd918bd3 100644
--- a/src/shrpx.cc
+++ b/src/shrpx.cc
@@ -1915,6 +1915,7 @@ int main(int argc, char **argv) {
          90},
         {SHRPX_OPT_REQUEST_PHASE_FILE, required_argument, &flag, 91},
         {SHRPX_OPT_RESPONSE_PHASE_FILE, required_argument, &flag, 92},
+        {SHRPX_OPT_ACCEPT_PROXY_PROTOCOL, no_argument, &flag, 93},
         {nullptr, 0, nullptr, 0}};
 
     int option_index = 0;
@@ -2316,6 +2317,10 @@ int main(int argc, char **argv) {
         // --response-phase-file
         cmdcfgs.emplace_back(SHRPX_OPT_RESPONSE_PHASE_FILE, optarg);
         break;
+      case 93:
+        // --accept-proxy-protocol
+        cmdcfgs.emplace_back(SHRPX_OPT_ACCEPT_PROXY_PROTOCOL, "yes");
+        break;
       default:
         break;
       }
diff --git a/src/shrpx_client_handler.cc b/src/shrpx_client_handler.cc
index 87c1659e..7d7f7a52 100644
--- a/src/shrpx_client_handler.cc
+++ b/src/shrpx_client_handler.cc
@@ -382,6 +382,16 @@ ClientHandler::ClientHandler(Worker *worker, int fd, SSL *ssl,
   conn_.rlimit.startw();
   ev_timer_again(conn_.loop, &conn_.rt);
 
+  if (get_config()->accept_proxy_protocol) {
+    read_ = write_ = &ClientHandler::read_clear;
+    on_read_ = &ClientHandler::proxy_protocol_read;
+    on_write_ = &ClientHandler::upstream_noop;
+  } else {
+    setup_upstream_io_callback();
+  }
+}
+
+void ClientHandler::setup_upstream_io_callback() {
   if (conn_.tls.ssl) {
     conn_.prepare_server_handshake();
     read_ = write_ = &ClientHandler::tls_handshake;
@@ -829,4 +839,185 @@ ev_io *ClientHandler::get_wev() { return &conn_.wev; }
 
 Worker *ClientHandler::get_worker() const { return worker_; }
 
+namespace {
+ssize_t parse_proxy_line_port(const uint8_t *first, const uint8_t *last) {
+  auto p = first;
+  int32_t port = 0;
+
+  for (; p != last && util::isDigit(*p); ++p) {
+    port *= 10;
+    port += *p - '0';
+
+    if (port > 65535) {
+      return -1;
+    }
+  }
+
+  return p - first;
+}
+} // namespace
+
+int ClientHandler::proxy_protocol_read() {
+  if (LOG_ENABLED(INFO)) {
+    CLOG(INFO, this) << "PROXY-protocol: Started";
+  }
+
+  auto first = rb_.pos;
+
+  // NULL character really destroys getaddrinfo function.  We won't
+  // expect it in PROXY protocol line, so find it here.
+  auto chrs = std::array<char, 2>{{'\r', '\0'}};
+  auto end = std::find_first_of(rb_.pos, rb_.pos + rb_.rleft(),
+                                std::begin(chrs), std::end(chrs));
+  if (end + 2 > rb_.pos + rb_.rleft() || *end == '\0' || end[1] != '\n') {
+    return -1;
+  }
+
+  constexpr const char HEADER[] = "PROXY ";
+
+  if (rb_.rleft() < str_size(HEADER)) {
+    if (LOG_ENABLED(INFO)) {
+      CLOG(INFO, this) << "PROXY-protocol-v1: PROXY version 1 ID not found";
+    }
+    return -1;
+  }
+
+  if (!util::streq_l(HEADER, rb_.pos, str_size(HEADER))) {
+    if (LOG_ENABLED(INFO)) {
+      CLOG(INFO, this) << "PROXY-protocol-v1: Bad PROXY protocol version 1 ID";
+    }
+    return -1;
+  }
+
+  rb_.drain(str_size(HEADER));
+
+  int family;
+
+  if (rb_.pos[0] == 'T') {
+    if (rb_.rleft() < 5) {
+      if (LOG_ENABLED(INFO)) {
+        CLOG(INFO, this) << "PROXY-protocol-v1: INET protocol family not found";
+      }
+      return -1;
+    }
+
+    if (util::streq_l("TCP4 ", rb_.pos, 5)) {
+      family = AF_INET;
+    } else if (util::streq_l("TCP6 ", rb_.pos, 5)) {
+      family = AF_INET6;
+    } else {
+      if (LOG_ENABLED(INFO)) {
+        CLOG(INFO, this) << "PROXY-protocol-v1: Unknown INET protocol family";
+      }
+      return -1;
+    }
+
+    rb_.drain(5);
+  } else {
+    if (rb_.rleft() < 7) {
+      if (LOG_ENABLED(INFO)) {
+        CLOG(INFO, this) << "PROXY-protocol-v1: INET protocol family not found";
+      }
+      return -1;
+    }
+    if (!util::streq_l("UNKNOWN", rb_.pos, 7)) {
+      if (LOG_ENABLED(INFO)) {
+        CLOG(INFO, this) << "PROXY-protocol-v1: Unknown INET protocol family";
+      }
+      return -1;
+    }
+
+    return 0;
+  }
+
+  // source address
+  auto token_end = std::find(rb_.pos, end, ' ');
+  if (token_end == end) {
+    if (LOG_ENABLED(INFO)) {
+      CLOG(INFO, this) << "PROXY-protocol-v1: Source address not found";
+    }
+    return -1;
+  }
+
+  *token_end = '\0';
+  if (!util::numeric_host(reinterpret_cast<const char *>(rb_.pos), family)) {
+    if (LOG_ENABLED(INFO)) {
+      CLOG(INFO, this) << "PROXY-protocol-v1: Invalid source address";
+    }
+    return -1;
+  }
+
+  auto src_addr = rb_.pos;
+  auto src_addrlen = token_end - rb_.pos;
+
+  rb_.drain(token_end - rb_.pos + 1);
+
+  // destination address
+  token_end = std::find(rb_.pos, end, ' ');
+  if (token_end == end) {
+    if (LOG_ENABLED(INFO)) {
+      CLOG(INFO, this) << "PROXY-protocol-v1: Destination address not found";
+    }
+    return -1;
+  }
+
+  *token_end = '\0';
+  if (!util::numeric_host(reinterpret_cast<const char *>(rb_.pos), family)) {
+    if (LOG_ENABLED(INFO)) {
+      CLOG(INFO, this) << "PROXY-protocol-v1: Invalid destination address";
+    }
+    return -1;
+  }
+
+  // Currently we don't use destination address
+
+  rb_.drain(token_end - rb_.pos + 1);
+
+  // source port
+  auto n = parse_proxy_line_port(rb_.pos, end);
+  if (n <= 0 || *(rb_.pos + n) != ' ') {
+    if (LOG_ENABLED(INFO)) {
+      CLOG(INFO, this) << "PROXY-protocol-v1: Invalid source port";
+    }
+    return -1;
+  }
+
+  rb_.pos[n] = '\0';
+  auto src_port = rb_.pos;
+  auto src_portlen = n;
+
+  rb_.drain(n + 1);
+
+  // destination  port
+  n = parse_proxy_line_port(rb_.pos, end);
+  if (n <= 0 || rb_.pos + n != end) {
+    if (LOG_ENABLED(INFO)) {
+      CLOG(INFO, this) << "PROXY-protocol-v1: Invalid destination port";
+    }
+    return -1;
+  }
+
+  // Currently we don't use destination port
+
+  rb_.drain(end + 2 - rb_.pos);
+
+  ipaddr_.assign(src_addr, src_addr + src_addrlen);
+  port_.assign(src_port, src_port + src_portlen);
+
+  if (LOG_ENABLED(INFO)) {
+    CLOG(INFO, this) << "PROXY-protocol-v1: Finished, " << (rb_.pos - first)
+                     << " bytes read";
+  }
+
+  setup_upstream_io_callback();
+
+  // Run on_read to process data left in buffer since they are not
+  // notified further
+  if (on_read() != 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
 } // namespace shrpx
diff --git a/src/shrpx_client_handler.h b/src/shrpx_client_handler.h
index 4d4ccd9c..45ef7a20 100644
--- a/src/shrpx_client_handler.h
+++ b/src/shrpx_client_handler.h
@@ -71,6 +71,8 @@ public:
   int upstream_http1_connhd_read();
   int upstream_write();
 
+  int proxy_protocol_read();
+
   // Performs I/O operation.  Internally calls on_read()/on_write().
   int do_read();
   int do_write();
@@ -130,6 +132,8 @@ public:
   void signal_write();
   ev_io *get_wev();
 
+  void setup_upstream_io_callback();
+
 private:
   Connection conn_;
   ev_timer reneg_shutdown_timer_;
diff --git a/src/shrpx_config.cc b/src/shrpx_config.cc
index ce2927b7..fb2d34ef 100644
--- a/src/shrpx_config.cc
+++ b/src/shrpx_config.cc
@@ -625,6 +625,7 @@ void parse_mapping(const DownstreamAddr &addr, const char *src) {
 
 // generated by gennghttpxfun.py
 enum {
+  SHRPX_OPTID_ACCEPT_PROXY_PROTOCOL,
   SHRPX_OPTID_ACCESSLOG_FILE,
   SHRPX_OPTID_ACCESSLOG_FORMAT,
   SHRPX_OPTID_ACCESSLOG_SYSLOG,
@@ -1099,6 +1100,11 @@ int option_lookup_token(const char *name, size_t namelen) {
         return SHRPX_OPTID_BACKEND_TLS_SNI_FIELD;
       }
       break;
+    case 'l':
+      if (util::strieq_l("accept-proxy-protoco", name, 20)) {
+        return SHRPX_OPTID_ACCEPT_PROXY_PROTOCOL;
+      }
+      break;
     case 'r':
       if (util::strieq_l("tls-ticket-key-ciphe", name, 20)) {
         return SHRPX_OPTID_TLS_TICKET_KEY_CIPHER;
@@ -1968,6 +1974,10 @@ int parse_config(const char *opt, const char *optarg,
     LOG(WARN) << opt
               << ": ignored because mruby support is disabled at build time.";
 #endif // !HAVE_MRUBY
+    return 0;
+  case SHRPX_OPTID_ACCEPT_PROXY_PROTOCOL:
+    mod_config()->accept_proxy_protocol = util::strieq(optarg, "yes");
+
     return 0;
   case SHRPX_OPTID_CONF:
     LOG(WARN) << "conf: ignored";
diff --git a/src/shrpx_config.h b/src/shrpx_config.h
index 2bbb9647..3da46dee 100644
--- a/src/shrpx_config.h
+++ b/src/shrpx_config.h
@@ -185,6 +185,7 @@ constexpr char SHRPX_OPT_TLS_TICKET_KEY_MEMCACHED_MAX_FAIL[] =
     "tls-ticket-key-memcached-max-fail";
 constexpr char SHRPX_OPT_REQUEST_PHASE_FILE[] = "request-phase-file";
 constexpr char SHRPX_OPT_RESPONSE_PHASE_FILE[] = "response-phase-file";
+constexpr char SHRPX_OPT_ACCEPT_PROXY_PROTOCOL[] = "accept-proxy-protocol";
 
 union sockaddr_union {
   sockaddr_storage storage;
@@ -409,6 +410,7 @@ struct Config {
   bool no_ocsp;
   // true if --tls-ticket-key-cipher is used
   bool tls_ticket_key_cipher_given;
+  bool accept_proxy_protocol;
 };
 
 const Config *get_config();
diff --git a/src/util.cc b/src/util.cc
index bfa292a8..9b709dbe 100644
--- a/src/util.cc
+++ b/src/util.cc
@@ -636,9 +636,13 @@ void write_uri_field(std::ostream &o, const char *uri, const http_parser_url &u,
 }
 
 bool numeric_host(const char *hostname) {
+  return numeric_host(hostname, AF_UNSPEC);
+}
+
+bool numeric_host(const char *hostname, int family) {
   struct addrinfo *res;
   struct addrinfo hints {};
-  hints.ai_family = AF_UNSPEC;
+  hints.ai_family = family;
   hints.ai_flags = AI_NUMERICHOST;
   if (getaddrinfo(hostname, nullptr, &hints, &res)) {
     return false;
diff --git a/src/util.h b/src/util.h
index 6463d19a..ab039235 100644
--- a/src/util.h
+++ b/src/util.h
@@ -512,6 +512,8 @@ void write_uri_field(std::ostream &o, const char *uri, const http_parser_url &u,
 
 bool numeric_host(const char *hostname);
 
+bool numeric_host(const char *hostname, int family);
+
 // Returns numeric address string of |addr|.  If getnameinfo() is
 // failed, "unknown" is returned.
 std::string numeric_name(const struct sockaddr *sa, socklen_t salen);