--- a/jdk/src/java.desktop/share/classes/com/sun/java/swing/plaf/windows/WindowsComboBoxUI.java	Mon Apr 24 10:49:43 2017 -0700
+++ b/jdk/src/java.desktop/share/classes/com/sun/java/swing/plaf/windows/WindowsComboBoxUI.java	Thu Apr 27 08:27:25 2017 -0700
@@ -339,11 +339,16 @@
     public Dimension getMinimumSize( JComponent c ) {
         Dimension d = super.getMinimumSize(c);
         if (XPStyle.getXP() != null) {
-            d.width += 5;
+            d.width += 7;
+            boolean isEditable = false;
+            if (c instanceof JComboBox) {
+                isEditable = ((JComboBox) c).isEditable();
+            }
+            d.height += isEditable ? 4 : 6;
         } else {
             d.width += 4;
+            d.height += 2;
         }
-        d.height += 2;
         return d;
     }
 

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/javax/swing/JComboBox/WindowsComboBoxSize/WindowsComboBoxSizeTest.java	Thu Apr 27 08:27:25 2017 -0700
@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8179027
+ * @requires (os.family == "windows")
+ * @summary JComboBox too small under Windows LAF
+ * @run main WindowsComboBoxSizeTest
+ */
+
+import javax.swing.*;
+import java.awt.FlowLayout;
+import java.awt.Robot;
+
+public class WindowsComboBoxSizeTest {
+    private static JTextField textField;
+    private static JComboBox<String> comboBox;
+    private static JComboBox<String> comboBoxEd;
+    private static JFrame frame;
+
+    public static void main(String[] args) throws Exception {
+        UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
+
+        SwingUtilities.invokeAndWait(() -> {
+            frame = new JFrame();
+            frame.getContentPane().setLayout( new FlowLayout() );
+
+            textField = new JTextField("item 1");
+            frame.getContentPane().add(textField);
+
+            comboBox = new JComboBox<>(new String[]
+                                                {"item 1", "item 2", "item 3"});
+            frame.getContentPane().add(comboBox);
+
+            comboBoxEd = new JComboBox<>(new String[]
+                                                {"item 1", "item 2", "item 3"});
+            comboBoxEd.setEditable( true );
+            frame.getContentPane().add(comboBoxEd);
+
+            frame.pack();
+            frame.setVisible( true );
+        });
+        Robot robot = new Robot();
+        robot.waitForIdle();
+
+        try {
+            test();
+        } finally {
+            SwingUtilities.invokeLater(frame::dispose);
+        }
+    }
+
+    private static void test() throws Exception {
+        SwingUtilities.invokeAndWait(() -> {
+            int expected = textField.getSize().height;
+            if (comboBox.getSize().height != expected ) {
+                throw new RuntimeException(
+                        "Wrong non-editable JComboBox height " +
+                                              comboBox.getSize().height);
+            }
+            if (comboBoxEd.getSize().height != expected ) {
+                throw new RuntimeException(
+                        "Wrong editable JComboBox height " +
+                                            comboBoxEd.getSize().height);
+            }
+        });
+    }
+}
+