diff --git a/pkg/labels/labels.go b/pkg/labels/labels.go
index 471677dbc..00afd6aea 100644
--- a/pkg/labels/labels.go
+++ b/pkg/labels/labels.go
@@ -112,6 +112,16 @@ func (ls Labels) Get(name string) string {
 	return ""
 }
 
+// Has returns if the label with the given name is present.
+func (ls Labels) Has(name string) bool {
+	for _, l := range ls {
+		if l.Name == name {
+			return true
+		}
+	}
+	return false
+}
+
 // Equal returns whether the two label sets are equal.
 func Equal(ls, o Labels) bool {
 	if len(ls) != len(o) {
diff --git a/scrape/scrape.go b/scrape/scrape.go
index a22dcb9a3..203910855 100644
--- a/scrape/scrape.go
+++ b/scrape/scrape.go
@@ -336,7 +336,7 @@ func (sp *scrapePool) mutateSampleLabels(lset labels.Labels, target *Target) lab
 
 	if sp.config.HonorLabels {
 		for _, l := range target.Labels() {
-			if lv := lset.Get(l.Name); lv == "" {
+			if !lset.Has(l.Name) {
 				lb.Set(l.Name, l.Value)
 			}
 		}
@@ -350,6 +350,12 @@ func (sp *scrapePool) mutateSampleLabels(lset labels.Labels, target *Target) lab
 		}
 	}
 
+	for _, l := range lb.Labels() {
+		if l.Value == "" {
+			lb.Del(l.Name)
+		}
+	}
+
 	res := lb.Labels()
 
 	if mrc := sp.config.MetricRelabelConfigs; len(mrc) > 0 {