diff --git a/ChangeLog b/ChangeLog
index 3f933aad90..a292a0d30f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+Sat May 21 14:25:38 2016  Kazuki Yamaguchi  <k@rhe.jp>
+
+	* ext/openssl/ossl_pkey_ec.c: rename PKey::EC#private_key? and
+	  #public_key? to #private? and #public? for consistency with other
+	  PKey types. Old names remain as alias.  [ruby-core:45541] [Bug #6567]
+
+	* test/openssl/test_pkey_ec.rb (test_check_key): check private? and
+	  public? works correctly.
+
 Sat May 21 12:40:36 2016  Kazuki Yamaguchi  <k@rhe.jp>
 
 	* ext/openssl/lib/openssl/buffering.rb (read_nonblock, readpartial):
diff --git a/ext/openssl/ossl_pkey_ec.c b/ext/openssl/ossl_pkey_ec.c
index d4153db68c..ef023b13f1 100644
--- a/ext/openssl/ossl_pkey_ec.c
+++ b/ext/openssl/ossl_pkey_ec.c
@@ -438,32 +438,34 @@ static VALUE ossl_ec_key_set_public_key(VALUE self, VALUE public_key)
 
 /*
  *  call-seq:
- *     key.public_key? => true or false
+ *     key.public? => true or false
  *
- *  Both public_key? and private_key? may return false at the same time unlike other PKey classes.
+ *  Returns whether this EC instance has a public key. The public key
+ *  (EC::Point) can be retrieved with EC#public_key.
  */
-static VALUE ossl_ec_key_is_public_key(VALUE self)
+static VALUE ossl_ec_key_is_public(VALUE self)
 {
     EC_KEY *ec;
 
     Require_EC_KEY(self, ec);
 
-    return (EC_KEY_get0_public_key(ec) ? Qtrue : Qfalse);
+    return EC_KEY_get0_public_key(ec) ? Qtrue : Qfalse;
 }
 
 /*
  *  call-seq:
- *     key.private_key? => true or false
+ *     key.private? => true or false
  *
- *  Both public_key? and private_key? may return false at the same time unlike other PKey classes.
+ *  Returns whether this EC instance has a private key. The private key (BN) can
+ *  be retrieved with EC#private_key.
  */
-static VALUE ossl_ec_key_is_private_key(VALUE self)
+static VALUE ossl_ec_key_is_private(VALUE self)
 {
     EC_KEY *ec;
 
     Require_EC_KEY(self, ec);
 
-    return (EC_KEY_get0_private_key(ec) ? Qtrue : Qfalse);
+    return EC_KEY_get0_private_key(ec) ? Qtrue : Qfalse;
 }
 
 static VALUE ossl_ec_key_to_string(VALUE self, VALUE ciph, VALUE pass, int format)
@@ -1619,8 +1621,10 @@ void Init_ossl_ec(void)
     rb_define_method(cEC, "private_key=", ossl_ec_key_set_private_key, 1);
     rb_define_method(cEC, "public_key", ossl_ec_key_get_public_key, 0);
     rb_define_method(cEC, "public_key=", ossl_ec_key_set_public_key, 1);
-    rb_define_method(cEC, "private_key?", ossl_ec_key_is_private_key, 0);
-    rb_define_method(cEC, "public_key?", ossl_ec_key_is_public_key, 0);
+    rb_define_method(cEC, "private?", ossl_ec_key_is_private, 0);
+    rb_define_method(cEC, "public?", ossl_ec_key_is_public, 0);
+    rb_define_alias(cEC, "private_key?", "private?");
+    rb_define_alias(cEC, "public_key?", "public?");
 /*  rb_define_method(cEC, "", ossl_ec_key_get_, 0);
     rb_define_method(cEC, "=", ossl_ec_key_set_ 1);
     set/get enc_flags
diff --git a/test/openssl/test_pkey_ec.rb b/test/openssl/test_pkey_ec.rb
index 23afed672a..302259b242 100644
--- a/test/openssl/test_pkey_ec.rb
+++ b/test/openssl/test_pkey_ec.rb
@@ -40,9 +40,21 @@ class OpenSSL::TestEC < OpenSSL::TestCase
 
   def test_check_key
     for key in @keys
-      assert_equal(key.check_key, true)
-      assert_equal(key.private_key?, true)
-      assert_equal(key.public_key?, true)
+      assert_equal(true, key.check_key)
+      assert_equal(true, key.private?)
+      assert_equal(true, key.public?)
+      key2 = OpenSSL::PKey::EC.new(key.group)
+      assert_equal(false, key2.private?)
+      assert_equal(false, key2.public?)
+      key2.public_key = key.public_key
+      assert_equal(false, key2.private?)
+      assert_equal(true, key2.public?)
+      key2.private_key = key.private_key
+      assert_equal(true, key2.private?)
+      assert_equal(true, key2.public?)
+      assert_equal(true, key2.check_key)
+      key2.private_key += 1
+      assert_raise(OpenSSL::PKey::ECError) { key2.check_key }
     end
   end