diff --git a/src/h2load.cc b/src/h2load.cc
index cad1f30b..4d795528 100644
--- a/src/h2load.cc
+++ b/src/h2load.cc
@@ -92,6 +92,8 @@ Config::Config()
       conn_active_timeout(0.),
       conn_inactivity_timeout(0.),
       no_tls_proto(PROTO_HTTP2),
+      header_table_size(4_k),
+      encoder_header_table_size(4_k),
       data_fd(-1),
       port(0),
       default_port(0),
@@ -1585,6 +1587,27 @@ std::unique_ptr<Worker> create_worker(uint32_t id, SSL_CTX *ssl_ctx,
 }
 } // namespace
 
+namespace {
+int parse_header_table_size(uint32_t &dst, const char *opt,
+                            const char *optarg) {
+  auto n = util::parse_uint_with_unit(optarg);
+  if (n == -1) {
+    std::cerr << "--" << opt << ": Bad option value: " << optarg << std::endl;
+    return -1;
+  }
+  if (n > std::numeric_limits<uint32_t>::max()) {
+    std::cerr << "--" << opt
+              << ": Value too large.  It should be less than or equal to "
+              << std::numeric_limits<uint32_t>::max() << std::endl;
+    return -1;
+  }
+
+  dst = n;
+
+  return 0;
+}
+} // namespace
+
 namespace {
 void print_version(std::ostream &out) {
   out << "h2load nghttp2/" NGHTTP2_VERSION << std::endl;
@@ -1755,6 +1778,15 @@ Options:
   --h1        Short        hand         for        --npn-list=http/1.1
               --no-tls-proto=http/1.1,    which   effectively    force
               http/1.1 for both http and https URI.
+  --header-table-size=<SIZE>
+              Specify decoder header table size.
+              Default: )" << config.header_table_size << R"(
+  --encoder-header-table-size=<SIZE>
+              Specify encoder header table size.  The decoder (server)
+              specifies  the maximum  dynamic table  size it  accepts.
+              Then the negotiated dynamic table size is the minimum of
+              this option value and the value which server specified.
+              Default: )" << config.encoder_header_table_size << R"(
   -v, --verbose
               Output debug information.
   --version   Display version information and exit.
@@ -1762,6 +1794,9 @@ Options:
 
 --
 
+  The <SIZE> argument is an integer and an optional unit (e.g., 10K is
+  10 * 1024).  Units are K, M and G (powers of 1024).
+
   The <DURATION> argument is an integer and an optional unit (e.g., 1s
   is 1 second and 500ms is 500 milliseconds).  Units are h, m, s or ms
   (hours, minutes, seconds and milliseconds, respectively).  If a unit
@@ -1803,6 +1838,8 @@ int main(int argc, char **argv) {
         {"npn-list", required_argument, &flag, 4},
         {"rate-period", required_argument, &flag, 5},
         {"h1", no_argument, &flag, 6},
+        {"header-table-size", required_argument, &flag, 7},
+        {"encoder-header-table-size", required_argument, &flag, 8},
         {nullptr, 0, nullptr, 0}};
     int option_index = 0;
     auto c = getopt_long(argc, argv, "hvW:c:d:m:n:p:t:w:H:i:r:T:N:B:",
@@ -2003,6 +2040,20 @@ int main(int argc, char **argv) {
             util::parse_config_str_list(StringRef::from_lit("http/1.1"));
         config.no_tls_proto = Config::PROTO_HTTP1_1;
         break;
+      case 7:
+        // --header-table-size
+        if (parse_header_table_size(config.header_table_size,
+                                    "header-table-size", optarg) != 0) {
+          exit(EXIT_FAILURE);
+        }
+        break;
+      case 8:
+        // --encoder-header-table-size
+        if (parse_header_table_size(config.encoder_header_table_size,
+                                    "encoder-header-table-size", optarg) != 0) {
+          exit(EXIT_FAILURE);
+        }
+        break;
       }
       break;
     default:
diff --git a/src/h2load.h b/src/h2load.h
index 39737805..0b84d2a6 100644
--- a/src/h2load.h
+++ b/src/h2load.h
@@ -96,6 +96,8 @@ struct Config {
     PROTO_SPDY3_1,
     PROTO_HTTP1_1
   } no_tls_proto;
+  uint32_t header_table_size;
+  uint32_t encoder_header_table_size;
   // file descriptor for upload data
   int data_fd;
   uint16_t port;
diff --git a/src/h2load_http2_session.cc b/src/h2load_http2_session.cc
index 0b780128..f7f63f17 100644
--- a/src/h2load_http2_session.cc
+++ b/src/h2load_http2_session.cc
@@ -206,21 +206,40 @@ void Http2Session::on_connect() {
 
   nghttp2_session_callbacks_set_send_callback(callbacks, send_callback);
 
-  nghttp2_session_client_new(&session_, callbacks, client_);
+  nghttp2_option *opt;
 
-  std::array<nghttp2_settings_entry, 2> iv;
+  rv = nghttp2_option_new(&opt);
+  assert(rv == 0);
+
+  auto config = client_->worker->config;
+
+  if (config->encoder_header_table_size != NGHTTP2_DEFAULT_HEADER_TABLE_SIZE) {
+    nghttp2_option_set_max_deflate_dynamic_table_size(
+        opt, config->encoder_header_table_size);
+  }
+
+  nghttp2_session_client_new2(&session_, callbacks, client_, opt);
+
+  nghttp2_option_del(opt);
+
+  std::array<nghttp2_settings_entry, 3> iv;
+  size_t niv = 2;
   iv[0].settings_id = NGHTTP2_SETTINGS_ENABLE_PUSH;
   iv[0].value = 0;
   iv[1].settings_id = NGHTTP2_SETTINGS_INITIAL_WINDOW_SIZE;
-  iv[1].value = (1 << client_->worker->config->window_bits) - 1;
+  iv[1].value = (1 << config->window_bits) - 1;
 
-  rv = nghttp2_submit_settings(session_, NGHTTP2_FLAG_NONE, iv.data(),
-                               iv.size());
+  if (config->header_table_size != NGHTTP2_DEFAULT_HEADER_TABLE_SIZE) {
+    iv[niv].settings_id = NGHTTP2_SETTINGS_HEADER_TABLE_SIZE;
+    iv[niv].value = config->header_table_size;
+    ++niv;
+  }
+
+  rv = nghttp2_submit_settings(session_, NGHTTP2_FLAG_NONE, iv.data(), niv);
 
   assert(rv == 0);
 
-  auto connection_window =
-      (1 << client_->worker->config->connection_window_bits) - 1;
+  auto connection_window = (1 << config->connection_window_bits) - 1;
   nghttp2_session_set_local_window_size(session_, NGHTTP2_FLAG_NONE, 0,
                                         connection_window);