diff --git a/lib/promscrape/scrapework.go b/lib/promscrape/scrapework.go
index 18ddb39052..16f460c239 100644
--- a/lib/promscrape/scrapework.go
+++ b/lib/promscrape/scrapework.go
@@ -767,6 +767,11 @@ func (sw *scrapeWork) applySeriesLimit(wc *writeRequestCtx) int {
 
 var sendStaleSeriesConcurrencyLimitCh = make(chan struct{}, cgroup.AvailableCPUs())
 
+// maxStaleSeriesAtOnce defines the max number of stale series
+// to process and send at once. It prevents from excessive memory usage
+// when big number of metrics become stale at the same time.
+const maxStaleSeriesAtOnce = 1e3
+
 func (sw *scrapeWork) sendStaleSeries(lastScrape, currScrape string, timestamp int64, addAutoSeries bool) {
 	// This function is CPU-bound, while it may allocate big amounts of memory.
 	// That's why it is a good idea to limit the number of concurrent calls to this function
@@ -790,35 +795,46 @@ func (sw *scrapeWork) sendStaleSeries(lastScrape, currScrape string, timestamp i
 	}()
 	if bodyString != "" {
 		wc.rows.UnmarshalWithErrLogger(bodyString, sw.logError)
-		srcRows := wc.rows.Rows
-		for i := range srcRows {
+	}
+
+	srcRows := wc.rows.Rows
+	for from := 0; from < len(srcRows); from += maxStaleSeriesAtOnce {
+		to := from + maxStaleSeriesAtOnce
+		if to > len(srcRows) {
+			to = len(srcRows)
+		}
+
+		for i := range srcRows[from:to] {
 			sw.addRowToTimeseries(wc, &srcRows[i], timestamp, true)
 		}
-	}
-	if addAutoSeries {
-		am := &autoMetrics{}
-		sw.addAutoMetrics(am, wc, timestamp)
-	}
 
-	// Apply series limit to stale markers in order to prevent sending stale markers for newly created series.
-	// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3660
-	if sw.seriesLimitExceeded {
-		sw.applySeriesLimit(wc)
-	}
-
-	series := wc.writeRequest.Timeseries
-	if len(series) == 0 {
-		return
-	}
-	// Substitute all the values with Prometheus stale markers.
-	for _, tss := range series {
-		samples := tss.Samples
-		for i := range samples {
-			samples[i].Value = decimal.StaleNaN
+		// add auto series at the last iteration
+		if addAutoSeries && to == len(srcRows) {
+			am := &autoMetrics{}
+			sw.addAutoMetrics(am, wc, timestamp)
 		}
-		staleSamplesCreated.Add(len(samples))
+
+		// Apply series limit to stale markers in order to prevent sending stale markers for newly created series.
+		// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3660
+		if sw.seriesLimitExceeded {
+			sw.applySeriesLimit(wc)
+		}
+
+		series := wc.writeRequest.Timeseries
+		if len(series) == 0 {
+			continue
+		}
+		// Substitute all the values with Prometheus stale markers.
+		for _, tss := range series {
+			samples := tss.Samples
+			for i := range samples {
+				samples[i].Value = decimal.StaleNaN
+			}
+			staleSamplesCreated.Add(len(samples))
+		}
+		sw.pushData(sw.Config.AuthToken, &wc.writeRequest)
+		wc.reset()
 	}
-	sw.pushData(sw.Config.AuthToken, &wc.writeRequest)
 }
 
 var staleSamplesCreated = metrics.NewCounter(`vm_promscrape_stale_samples_created_total`)
diff --git a/lib/promscrape/scrapework_test.go b/lib/promscrape/scrapework_test.go
index b94ba1dd1f..38a3a3462a 100644
--- a/lib/promscrape/scrapework_test.go
+++ b/lib/promscrape/scrapework_test.go
@@ -686,6 +686,44 @@ func TestAddRowToTimeseriesNoRelabeling(t *testing.T) {
 		`metric{a="e",foo="bar"} 0 123`)
 }
 
+func TestSendStaleSeries(t *testing.T) {
+	var sw scrapeWork
+	sw.Config = &ScrapeWork{
+		NoStaleMarkers: false,
+	}
+
+	var timeseriesExpectedN int
+	sw.PushData = func(at *auth.Token, wr *prompbmarshal.WriteRequest) {
+		t.Helper()
+		if len(wr.Timeseries) != timeseriesExpectedN {
+			t.Fatalf("expected to get %d stale series; got %d", timeseriesExpectedN, len(wr.Timeseries))
+		}
+	}
+
+	generateScrape := func(n int) string {
+		w := strings.Builder{}
+		for i := 0; i < n; i++ {
+			w.WriteString(fmt.Sprintf("foo_%d 1\n", i))
+		}
+		return w.String()
+	}
+
+	timeseriesExpectedN = 0
+	sw.sendStaleSeries("", "", 0, false)
+
+	timeseriesExpectedN = 0
+	sw.sendStaleSeries(generateScrape(10), generateScrape(10), 0, false)
+
+	timeseriesExpectedN = 10
+	sw.sendStaleSeries(generateScrape(10), "", 0, false)
+
+	timeseriesExpectedN = 5
+	sw.sendStaleSeries(generateScrape(10), generateScrape(5), 0, false)
+
+	timeseriesExpectedN = maxStaleSeriesAtOnce
+	sw.sendStaleSeries(generateScrape(maxStaleSeriesAtOnce*2), "", 0, false)
+}
+
 func parsePromRow(data string) *parser.Row {
 	var rows parser.Rows
 	errLogger := func(s string) {