diff --git a/lib/promscrape/client.go b/lib/promscrape/client.go
index d809bbaab5..e379a24b02 100644
--- a/lib/promscrape/client.go
+++ b/lib/promscrape/client.go
@@ -322,6 +322,11 @@ func (c *client) ReadData(dst []byte) ([]byte, error) {
 	} else if !swapResponseBodies {
 		dst = append(dst, resp.Body()...)
 	}
+	if len(dst) > c.hc.MaxResponseBodySize {
+		maxScrapeSizeExceeded.Inc()
+		return dst, fmt.Errorf("the response from %q exceeds -promscrape.maxScrapeSize=%d; "+
+			"either reduce the response size for the target or increase -promscrape.maxScrapeSize", c.scrapeURL, maxScrapeSize.N)
+	}
 	fasthttp.ReleaseResponse(resp)
 	if statusCode != fasthttp.StatusOK {
 		metrics.GetOrCreateCounter(fmt.Sprintf(`vm_promscrape_scrapes_total{status_code="%d"}`, statusCode)).Inc()