diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/GcTemporaryFilesTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/GcTemporaryFilesTest.java
new file mode 100644
index 000000000..59d544e63
--- /dev/null
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/GcTemporaryFilesTest.java
@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2017 Ericsson
+ * and other copyright owners as documented in the project's IP log.
+ *
+ * This program and the accompanying materials are made available
+ * under the terms of the Eclipse Distribution License v1.0 which
+ * accompanies this distribution, is reproduced below, and is
+ * available at http://www.eclipse.org/org/documents/edl-v10.php
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ *
+ * - Neither the name of the Eclipse Foundation, Inc. nor the
+ *   names of its contributors may be used to endorse or promote
+ *   products derived from this software without specific prior
+ *   written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package org.eclipse.jgit.internal.storage.file;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+import java.io.File;
+import java.nio.file.Paths;
+import java.time.Instant;
+
+import org.junit.Before;
+import org.junit.Test;
+
+public class GcTemporaryFilesTest extends GcTestCase {
+	private static final String TEMP_IDX = "gc_1234567890.idx_tmp";
+
+	private static final String TEMP_PACK = "gc_1234567890.pack_tmp";
+
+	private File packDir;
+
+	@Override
+	@Before
+	public void setUp() throws Exception {
+		super.setUp();
+		packDir = Paths.get(repo.getObjectsDirectory().getAbsolutePath(),
+				"pack").toFile(); //$NON-NLS-1$
+	}
+
+	@Test
+	public void oldTempPacksAndIdxAreDeleted() throws Exception {
+		File tempIndex = new File(packDir, TEMP_IDX);
+		File tempPack = new File(packDir, TEMP_PACK);
+		if (!packDir.exists() || !packDir.isDirectory()) {
+			assertTrue(packDir.mkdirs());
+		}
+		assertTrue(tempPack.createNewFile());
+		assertTrue(tempIndex.createNewFile());
+		assertTrue(tempIndex.exists());
+		assertTrue(tempPack.exists());
+		long _24HoursBefore = Instant.now().toEpochMilli()
+				- 24 * 60 * 62 * 1000;
+		tempIndex.setLastModified(_24HoursBefore);
+		tempPack.setLastModified(_24HoursBefore);
+		gc.gc();
+		assertFalse(tempIndex.exists());
+		assertFalse(tempPack.exists());
+	}
+
+	@Test
+	public void recentTempPacksAndIdxAreNotDeleted() throws Exception {
+		File tempIndex = new File(packDir, TEMP_IDX);
+		File tempPack = new File(packDir, TEMP_PACK);
+		if (!packDir.exists() || !packDir.isDirectory()) {
+			assertTrue(packDir.mkdirs());
+		}
+		assertTrue(tempPack.createNewFile());
+		assertTrue(tempIndex.createNewFile());
+		assertTrue(tempIndex.exists());
+		assertTrue(tempPack.exists());
+		gc.gc();
+		assertTrue(tempIndex.exists());
+		assertTrue(tempPack.exists());
+	}
+}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/GC.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/GC.java
index 13d97528c..5f3167176 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/GC.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/GC.java
@@ -60,6 +60,8 @@
 import java.nio.file.StandardCopyOption;
 import java.text.MessageFormat;
 import java.text.ParseException;
+import java.time.Instant;
+import java.time.temporal.ChronoUnit;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -902,6 +904,7 @@ public Collection<PackFile> repack() throws IOException {
 		}
 		prunePacked();
 		deleteOrphans();
+		deleteTempPacksIdx();
 
 		lastPackedRefs = refsBefore;
 		lastRepackTime = time;
@@ -957,6 +960,27 @@ private void deleteOrphans() {
 		}
 	}
 
+	private void deleteTempPacksIdx() {
+		Path packDir = repo.getObjectDatabase().getPackDirectory().toPath();
+		Instant threshold = Instant.now().minus(1, ChronoUnit.DAYS);
+		try {
+			Files.newDirectoryStream(packDir, "gc_*_tmp") //$NON-NLS-1$
+					.forEach(t -> {
+						try {
+							Instant lastModified = Files.getLastModifiedTime(t)
+									.toInstant();
+							if (lastModified.isBefore(threshold)) {
+								Files.deleteIfExists(t);
+							}
+						} catch (IOException e) {
+							LOG.error(e.getMessage(), e);
+						}
+					});
+		} catch (IOException e) {
+			LOG.error(e.getMessage(), e);
+		}
+	}
+
 	/**
 	 * @param ref
 	 *            the ref which log should be inspected