diff --git a/src/shrpx_listen_handler.cc b/src/shrpx_listen_handler.cc
index ef158c0c..4fa7bab9 100644
--- a/src/shrpx_listen_handler.cc
+++ b/src/shrpx_listen_handler.cc
@@ -49,7 +49,6 @@ ListenHandler::ListenHandler(event_base *evbase, SSL_CTX *sv_ssl_ctx,
   : evbase_(evbase),
     sv_ssl_ctx_(sv_ssl_ctx),
     cl_ssl_ctx_(cl_ssl_ctx),
-    workers_(nullptr),
     http2session_(nullptr),
     rate_limit_group_(bufferevent_rate_limit_group_new
                       (evbase, get_config()->worker_rate_limit_cfg)),
@@ -65,7 +64,7 @@ ListenHandler::~ListenHandler()
 
 void ListenHandler::create_worker_thread(size_t num)
 {
-  workers_ = new WorkerInfo[num];
+  workers_.resize(num);
   num_worker_ = 0;
   for(size_t i = 0; i < num; ++i) {
     int rv;
diff --git a/src/shrpx_listen_handler.h b/src/shrpx_listen_handler.h
index 0d8e5a60..5b99cf81 100644
--- a/src/shrpx_listen_handler.h
+++ b/src/shrpx_listen_handler.h
@@ -31,6 +31,7 @@
 #include <sys/socket.h>
 
 #include <memory>
+#include <vector>
 
 #include <openssl/ssl.h>
 
@@ -58,12 +59,12 @@ public:
   event_base* get_evbase() const;
   int create_http2_session();
 private:
+  std::vector<WorkerInfo> workers_;
   event_base *evbase_;
   // The frontend server SSL_CTX
   SSL_CTX *sv_ssl_ctx_;
   // The backend server SSL_CTX
   SSL_CTX *cl_ssl_ctx_;
-  WorkerInfo *workers_;
   // Shared backend HTTP2 session. NULL if multi-threaded. In
   // multi-threaded case, see shrpx_worker.cc.
   Http2Session *http2session_;