diff --git a/jerry-core/ecma/base/ecma-helpers-string.c b/jerry-core/ecma/base/ecma-helpers-string.c
index 181e70962..8b340ab75 100644
--- a/jerry-core/ecma/base/ecma-helpers-string.c
+++ b/jerry-core/ecma/base/ecma-helpers-string.c
@@ -229,7 +229,7 @@ ecma_new_ecma_string_from_utf8_converted_to_cesu8 (const lit_utf8_byte_t *string
 
   ecma_string_t *string_desc_p = NULL;
 
-  ecma_length_t string_length = 0;
+  ecma_length_t converted_string_length = 0;
   lit_utf8_size_t converted_string_size = 0;
   lit_utf8_size_t pos = 0;
 
@@ -253,9 +253,10 @@ ecma_new_ecma_string_from_utf8_converted_to_cesu8 (const lit_utf8_byte_t *string
       JERRY_ASSERT ((string_p[pos] & LIT_UTF8_4_BYTE_MASK) == LIT_UTF8_4_BYTE_MARKER);
       pos += 4;
       converted_string_size += 2;
+      converted_string_length++;
     }
 
-    string_length++;
+    converted_string_length++;
   }
 
   JERRY_ASSERT (pos == string_size);
@@ -279,7 +280,7 @@ ecma_new_ecma_string_from_utf8_converted_to_cesu8 (const lit_utf8_byte_t *string
       string_desc_p->refs_and_container = ECMA_STRING_CONTAINER_HEAP_UTF8_STRING | ECMA_STRING_REF_ONE;
       string_desc_p->u.common_field = 0;
       string_desc_p->u.utf8_string.size = (uint16_t) converted_string_size;
-      string_desc_p->u.utf8_string.length = (uint16_t) string_length;
+      string_desc_p->u.utf8_string.length = (uint16_t) converted_string_length;
 
       data_p = (lit_utf8_byte_t *) (string_desc_p + 1);
     }
@@ -292,7 +293,7 @@ ecma_new_ecma_string_from_utf8_converted_to_cesu8 (const lit_utf8_byte_t *string
       string_desc_p->u.long_utf8_string_size = converted_string_size;
 
       ecma_long_string_t *long_string_desc_p = (ecma_long_string_t *) string_desc_p;
-      long_string_desc_p->long_utf8_string_length = string_length;
+      long_string_desc_p->long_utf8_string_length = converted_string_length;
 
       data_p = (lit_utf8_byte_t *) (long_string_desc_p + 1);
     }
diff --git a/tests/unit/test-api.c b/tests/unit/test-api.c
index bb31a2853..f515d5514 100644
--- a/tests/unit/test-api.c
+++ b/tests/unit/test-api.c
@@ -357,6 +357,13 @@ main (void)
   jerry_release_value (args[0]);
   jerry_release_value (args[1]);
 
+  // Test create_jerry_string_from_utf8 with 4-byte long unicode sequences
+  args[0] = jerry_create_string_from_utf8 ((jerry_char_t *) "\x73\x74\x72\x3a\xf0\x9d\x94\xa3\xf0\x9d\x94\xa4");
+  jerry_length_t cesu8_length = jerry_get_string_length (args[0]);
+
+  TEST_ASSERT (cesu8_length == 8);
+  jerry_release_value (args[0]);
+
   // Get global.boo (non-existing field)
   val_t = get_property (global_obj_val, "boo");
   TEST_ASSERT (!jerry_value_has_error_flag (val_t));