diff --git a/CHANGELOG.asciidoc b/CHANGELOG.asciidoc
index 495cf9156532..6738a1339365 100644
--- a/CHANGELOG.asciidoc
+++ b/CHANGELOG.asciidoc
@@ -63,6 +63,7 @@ https://github.com/elastic/beats/compare/v6.0.0-beta2...master[Check the HEAD di
 - Fix the fetching of process information when some data is missing under MacOS X. {issue}5337[5337]
 - Change `MySQL active connections` visualization title to `MySQL total connections`. {issue}4812[4812]
 - Fix map overwrite in docker diskio module. {issue}5582[5582]
+- Fix connection leak in mongodb module. {issue}5688[5688]
 
 *Packetbeat*
 
diff --git a/metricbeat/module/mongodb/dbstats/dbstats.go b/metricbeat/module/mongodb/dbstats/dbstats.go
index 9af1a9aadfb4..19beedb75236 100644
--- a/metricbeat/module/mongodb/dbstats/dbstats.go
+++ b/metricbeat/module/mongodb/dbstats/dbstats.go
@@ -61,6 +61,7 @@ func (m *MetricSet) Fetch() ([]common.MapStr, error) {
 	if err != nil {
 		return nil, err
 	}
+	defer mongoSession.Close()
 
 	// Get the list of databases names, which we'll use to call db.stats() on each
 	dbNames, err := mongoSession.DatabaseNames()
diff --git a/metricbeat/module/mongodb/status/status.go b/metricbeat/module/mongodb/status/status.go
index bc522d52ba08..9d3711d52019 100644
--- a/metricbeat/module/mongodb/status/status.go
+++ b/metricbeat/module/mongodb/status/status.go
@@ -63,6 +63,7 @@ func (m *MetricSet) Fetch() (common.MapStr, error) {
 	if err != nil {
 		return nil, err
 	}
+	defer mongoSession.Close()
 
 	result := map[string]interface{}{}
 	if err := mongoSession.DB("admin").Run(bson.D{{Name: "serverStatus", Value: 1}}, &result); err != nil {