diff --git a/flow_db.c b/flow_db.c
index 8663980..88ce971 100644
--- a/flow_db.c
+++ b/flow_db.c
@@ -40,9 +40,25 @@ struct ip_pair *pairs [HASH_TBL_SIZE];
 
 void init_hash_table(void)
 {
-	bzero(pairs, sizeof(struct ip_pair *) * HASH_TBL_SIZE);
+	memset(pairs, 0, sizeof(struct ip_pair *) * HASH_TBL_SIZE);
 }
 
+void free_hash_table(void)
+{
+	size_t b;
+	struct ip_pair *curp;
+
+	for (b = 0; b < HASH_TBL_SIZE; b++) {
+		while (pairs[b]) {
+			curp = pairs[b];
+			pairs[b] = pairs[b]->next;
+			reset_pdf(&curp->pdf);
+			free(curp);
+		}
+	}
+
+	init_hash_table();
+}
 
 static unsigned int hashf(const void *key, size_t sz, unsigned int hash)
 {
diff --git a/pkt2flow.c b/pkt2flow.c
index 7bd23ba..7ab5bcd 100644
--- a/pkt2flow.c
+++ b/pkt2flow.c
@@ -329,5 +329,6 @@ int main(int argc, char *argv[])
 	init_hash_table();
 	process_trace();
 	close_trace_files();
+	free_hash_table();
 	exit(0);
 }
diff --git a/pkt2flow.h b/pkt2flow.h
index 1f93935..61a2cd9 100644
--- a/pkt2flow.h
+++ b/pkt2flow.h
@@ -93,6 +93,11 @@ char *new_file_name(uint32_t src_ip, uint32_t dst_ip,
  */
 void init_hash_table(void);
 
+/*
+ * Free the flow has table
+ */
+void free_hash_table(void);
+
 /*
  * Search for the flow in the flow hash table with specific 4-tuple;
  * If the flow item exists in the hash table, the pointer to the ip_pair will be