diff --git a/tests/nghttp2_hd_test.c b/tests/nghttp2_hd_test.c
index 503bbadf..32676f78 100644
--- a/tests/nghttp2_hd_test.c
+++ b/tests/nghttp2_hd_test.c
@@ -1278,10 +1278,11 @@ void test_nghttp2_hd_deflate_hd_vec(void) {
   uint8_t buf[4096];
   ssize_t blocklen;
   nghttp2_mem *mem;
-  nghttp2_vec vec[2];
+  nghttp2_vec vec[256];
   size_t buflen;
   nghttp2_bufs bufs;
   nva_out out;
+  size_t i;
 
   mem = nghttp2_mem_default();
 
@@ -1297,8 +1298,7 @@ void test_nghttp2_hd_deflate_hd_vec(void) {
   vec[1].base = &buf[buflen / 2];
   vec[1].len = buflen / 2;
 
-  blocklen =
-      nghttp2_hd_deflate_hd_vec(deflater, vec, ARRLEN(vec), nva, ARRLEN(nva));
+  blocklen = nghttp2_hd_deflate_hd_vec(deflater, vec, 2, nva, ARRLEN(nva));
 
   CU_ASSERT(blocklen > 0);
 
@@ -1336,8 +1336,7 @@ void test_nghttp2_hd_deflate_hd_vec(void) {
   nghttp2_hd_deflate_new(&deflater, 4096);
   nghttp2_hd_inflate_new(&inflater);
 
-  blocklen =
-      nghttp2_hd_deflate_hd_vec(deflater, vec, ARRLEN(vec), nva, ARRLEN(nva));
+  blocklen = nghttp2_hd_deflate_hd_vec(deflater, vec, 2, nva, ARRLEN(nva));
 
   CU_ASSERT(NGHTTP2_ERR_INSUFF_BUFSIZE == blocklen);
 
@@ -1355,13 +1354,42 @@ void test_nghttp2_hd_deflate_hd_vec(void) {
   vec[1].base = &buf[buflen / 2];
   vec[1].len = (buflen / 2) - 1;
 
-  blocklen =
-      nghttp2_hd_deflate_hd_vec(deflater, vec, ARRLEN(vec), nva, ARRLEN(nva));
+  blocklen = nghttp2_hd_deflate_hd_vec(deflater, vec, 2, nva, ARRLEN(nva));
 
   CU_ASSERT(NGHTTP2_ERR_INVALID_ARGUMENT == blocklen);
 
   nghttp2_hd_inflate_del(inflater);
   nghttp2_hd_deflate_del(deflater);
+
+  /* check the case where chunk size is 1 */
+  nghttp2_hd_deflate_new(&deflater, 4096);
+  nghttp2_hd_inflate_new(&inflater);
+
+  buflen = nghttp2_hd_deflate_bound(deflater, nva, ARRLEN(nva));
+
+  assert(buflen <= ARRLEN(vec));
+
+  for (i = 0; i < buflen; ++i) {
+    vec[i].base = &buf[i];
+    vec[i].len = 1;
+  }
+
+  blocklen = nghttp2_hd_deflate_hd_vec(deflater, vec, buflen, nva, ARRLEN(nva));
+
+  CU_ASSERT(blocklen > 0);
+
+  nghttp2_bufs_wrap_init(&bufs, buf, (size_t)blocklen, mem);
+  bufs.head->buf.last += blocklen;
+
+  CU_ASSERT(blocklen == inflate_hd(inflater, &out, &bufs, 0, mem));
+  CU_ASSERT(ARRLEN(nva) == out.nvlen);
+  assert_nv_equal(nva, out.nva, ARRLEN(nva), mem);
+
+  nghttp2_bufs_wrap_free(&bufs);
+
+  nghttp2_hd_inflate_del(inflater);
+  nghttp2_hd_deflate_del(deflater);
+  nva_out_reset(&out, mem);
 }
 
 static size_t encode_length(uint8_t *buf, uint64_t n, size_t prefix) {