diff --git a/CHANGES.txt b/CHANGES.txt
index 4d2ef6c3d4..c4fde4445e 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -106,6 +106,7 @@
  * Add the ability to disable bulk loading of SSTables (CASSANDRA-18781)
  * Clean up obsolete functions and simplify cql_version handling in cqlsh (CASSANDRA-18787)
 Merged from 5.0:
+ * Add flag to avoid invalidating key cache on sstable deletions (CASSANDRA-20068)
  * Interpret inet, bigint, varint, and decimal as non-reversed types for query construction and post-filtering (CASSANDRA-20100)
  * Streamline the serialized format for index status gossip messages (CASSANDRA-20058)
  * Batch clusterings into single SAI partition post-filtering reads (CASSANDRA-19497)
diff --git a/src/java/org/apache/cassandra/config/Config.java b/src/java/org/apache/cassandra/config/Config.java
index ca4cf09be4..9335953d20 100644
--- a/src/java/org/apache/cassandra/config/Config.java
+++ b/src/java/org/apache/cassandra/config/Config.java
@@ -464,6 +464,7 @@ public class Config
     public volatile DataStorageSpec.IntMebibytesBound sstable_preemptive_open_interval = new DataStorageSpec.IntMebibytesBound("50MiB");
 
     public volatile boolean key_cache_migrate_during_compaction = true;
+    public volatile boolean key_cache_invalidate_after_sstable_deletion = false;
     public volatile int key_cache_keys_to_save = Integer.MAX_VALUE;
     @Replaces(oldName = "key_cache_size_in_mb", converter = Converters.MEBIBYTES_DATA_STORAGE_LONG, deprecated = true)
     public DataStorageSpec.LongMebibytesBound key_cache_size = null;
diff --git a/src/java/org/apache/cassandra/config/DatabaseDescriptor.java b/src/java/org/apache/cassandra/config/DatabaseDescriptor.java
index 3cd003b97b..f80dcfd5b5 100644
--- a/src/java/org/apache/cassandra/config/DatabaseDescriptor.java
+++ b/src/java/org/apache/cassandra/config/DatabaseDescriptor.java
@@ -3841,6 +3841,16 @@ public class DatabaseDescriptor
         conf.key_cache_migrate_during_compaction = migrateCacheEntry;
     }
 
+    public static boolean shouldInvalidateKeycacheOnSSTableDeletion()
+    {
+        return conf.key_cache_invalidate_after_sstable_deletion;
+    }
+
+    public static void setInvalidateKeycacheOnSSTableDeletion(boolean invalidateCacheEntry)
+    {
+        conf.key_cache_invalidate_after_sstable_deletion = invalidateCacheEntry;
+    }
+
     /**
      * This method can return negative number for disabled
      */
diff --git a/src/java/org/apache/cassandra/io/sstable/format/big/BigFormat.java b/src/java/org/apache/cassandra/io/sstable/format/big/BigFormat.java
index 585e6c389c..795678841a 100644
--- a/src/java/org/apache/cassandra/io/sstable/format/big/BigFormat.java
+++ b/src/java/org/apache/cassandra/io/sstable/format/big/BigFormat.java
@@ -340,13 +340,16 @@ public class BigFormat extends AbstractSSTableFormat<BigTableReader, BigTableWri
     {
         try
         {
-            // remove key cache entries for the sstable being deleted
-            Iterator<KeyCacheKey> it = CacheService.instance.keyCache.keyIterator();
-            while (it.hasNext())
+            if (DatabaseDescriptor.shouldInvalidateKeycacheOnSSTableDeletion())
             {
-                KeyCacheKey key = it.next();
-                if (key.desc.equals(desc))
-                    it.remove();
+                // remove key cache entries for the sstable being deleted
+                Iterator<KeyCacheKey> it = CacheService.instance.keyCache.keyIterator();
+                while (it.hasNext())
+                {
+                    KeyCacheKey key = it.next();
+                    if (key.desc.equals(desc))
+                        it.remove();
+                }
             }
 
             delete(desc, Lists.newArrayList(Sets.intersection(allComponents(), desc.discoverComponents())));
diff --git a/src/java/org/apache/cassandra/service/StorageService.java b/src/java/org/apache/cassandra/service/StorageService.java
index 9c20aa262d..47bb83a5ec 100644
--- a/src/java/org/apache/cassandra/service/StorageService.java
+++ b/src/java/org/apache/cassandra/service/StorageService.java
@@ -4502,6 +4502,16 @@ public class StorageService extends NotificationBroadcasterSupport implements IE
         DatabaseDescriptor.setMigrateKeycacheOnCompaction(invalidateKeyCacheOnCompaction);
     }
 
+    public boolean getInvalidateKeycacheOnSSTableDeletion()
+    {
+        return DatabaseDescriptor.shouldInvalidateKeycacheOnSSTableDeletion();
+    }
+
+    public void setInvalidateKeycacheOnSSTableDeletion(boolean invalidate)
+    {
+        DatabaseDescriptor.setInvalidateKeycacheOnSSTableDeletion(invalidate);
+    }
+
     public int getTombstoneWarnThreshold()
     {
         return DatabaseDescriptor.getTombstoneWarnThreshold();
diff --git a/src/java/org/apache/cassandra/service/StorageServiceMBean.java b/src/java/org/apache/cassandra/service/StorageServiceMBean.java
index 2a9096762a..1529a59a56 100644
--- a/src/java/org/apache/cassandra/service/StorageServiceMBean.java
+++ b/src/java/org/apache/cassandra/service/StorageServiceMBean.java
@@ -850,6 +850,8 @@ public interface StorageServiceMBean extends NotificationEmitter
 
     public boolean getMigrateKeycacheOnCompaction();
     public void setMigrateKeycacheOnCompaction(boolean invalidateKeyCacheOnCompaction);
+    public boolean getInvalidateKeycacheOnSSTableDeletion();
+    public void setInvalidateKeycacheOnSSTableDeletion(boolean invalidate);
 
     public int getConcurrentViewBuilders();
     public void setConcurrentViewBuilders(int value);
diff --git a/test/unit/org/apache/cassandra/io/sstable/keycache/KeyCacheTest.java b/test/unit/org/apache/cassandra/io/sstable/keycache/KeyCacheTest.java
index 15c37ea60a..abe83b59d5 100644
--- a/test/unit/org/apache/cassandra/io/sstable/keycache/KeyCacheTest.java
+++ b/test/unit/org/apache/cassandra/io/sstable/keycache/KeyCacheTest.java
@@ -350,14 +350,14 @@ public class KeyCacheTest
 
         LifecycleTransaction.waitForDeletions();
 
-        // after releasing the reference this should drop to 2
-        assertKeyCacheSize(2, KEYSPACE1, cf);
+        // after releasing the reference this should drop to 2, unless we don't invalidate keycache on sstable deletion
+        assertKeyCacheSize(DatabaseDescriptor.shouldInvalidateKeycacheOnSSTableDeletion() ? 2 : 4, KEYSPACE1, cf);
 
         // re-read same keys to verify that key cache didn't grow further
         Util.getAll(Util.cmd(cfs, "key1").build());
         Util.getAll(Util.cmd(cfs, "key2").build());
 
-        assertKeyCacheSize( 2, KEYSPACE1, cf);
+        assertKeyCacheSize( DatabaseDescriptor.shouldInvalidateKeycacheOnSSTableDeletion() ? 2 : 4, KEYSPACE1, cf);
     }
 
     @Test