diff --git a/CHANGES.txt b/CHANGES.txt
index 2f945bb09e..088daa7c81 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,4 +1,5 @@
 1.1.7
+ * expunge row cache post-truncate (CASSANDRA-4940)
  * remove IAuthority2 (CASSANDRA-4875)
  * add get[Row|Key]CacheEntries to CacheServiceMBean (CASSANDRA-4859)
  * fix get_paged_slice to wrap to next row correctly (CASSANDRA-4816)
diff --git a/src/java/org/apache/cassandra/db/compaction/CompactionManager.java b/src/java/org/apache/cassandra/db/compaction/CompactionManager.java
index fcdf45bdb8..edfea0a31f 100644
--- a/src/java/org/apache/cassandra/db/compaction/CompactionManager.java
+++ b/src/java/org/apache/cassandra/db/compaction/CompactionManager.java
@@ -32,6 +32,7 @@ import javax.management.MBeanServer;
 import javax.management.ObjectName;
 
 import org.apache.cassandra.cache.AutoSavingCache;
+import org.apache.cassandra.cache.RowCacheKey;
 import org.apache.cassandra.concurrent.DebuggableThreadPoolExecutor;
 import org.apache.cassandra.concurrent.NamedThreadFactory;
 import org.apache.cassandra.config.CFMetaData;
@@ -48,6 +49,7 @@ import org.apache.cassandra.io.sstable.*;
 import org.apache.cassandra.io.util.FileUtils;
 import org.apache.cassandra.io.util.RandomAccessReader;
 import org.apache.cassandra.service.AntiEntropyService;
+import org.apache.cassandra.service.CacheService;
 import org.apache.cassandra.service.StorageService;
 import org.apache.cassandra.utils.*;
 import org.slf4j.Logger;
@@ -813,6 +815,12 @@ public class CompactionManager implements CompactionManagerMBean
 
                     for (SecondaryIndex index : main.indexManager.getIndexes())
                         index.truncate(truncatedAt);
+
+                    for (RowCacheKey key : CacheService.instance.rowCache.getKeySet())
+                    {
+                        if (key.cfId == main.metadata.cfId)
+                            CacheService.instance.rowCache.remove(key);
+                    }
                 }
                 finally
                 {