diff --git a/lib/promscrape/config.go b/lib/promscrape/config.go
index afd611872..d193b4b8f 100644
--- a/lib/promscrape/config.go
+++ b/lib/promscrape/config.go
@@ -4,7 +4,6 @@ import (
 	"encoding/json"
 	"flag"
 	"fmt"
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/auth"
 	"net/url"
 	"path/filepath"
 	"sort"
@@ -13,6 +12,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/auth"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/cgroup"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/envtemplate"
@@ -904,7 +904,7 @@ func getScrapeWorkConfig(sc *ScrapeConfig, baseDir string, globalCfg *GlobalConf
 	if metricsPath == "" {
 		metricsPath = "/metrics"
 	}
-	scheme := sc.Scheme
+	scheme := strings.ToLower(sc.Scheme)
 	if scheme == "" {
 		scheme = "http"
 	}