diff --git a/mainline/alpine-slim/Dockerfile b/mainline/alpine-slim/Dockerfile
index 9d1c1709f1b03eeb01afd9fcc59fd898c28047b5..44fb1f3571a975a9f86a04011170de8025466a63 100644
--- a/mainline/alpine-slim/Dockerfile
+++ b/mainline/alpine-slim/Dockerfile
@@ -3,7 +3,7 @@
 #
 # PLEASE DO NOT EDIT IT DIRECTLY.
 #
-FROM alpine:3.19
+FROM alpine:3.20
 
 LABEL maintainer="NGINX Docker Maintainers <docker-maint@nginx.com>"
 
diff --git a/update.sh b/update.sh
index a075b0754ec2b20f8eea033f94834a876d3dcc4a..d5ebc2ce78c8210a7c357a2e28039cbad1096c24 100755
--- a/update.sh
+++ b/update.sh
@@ -55,7 +55,7 @@ declare -A debian=(
 )
 
 declare -A alpine=(
-    [mainline]='3.19'
+    [mainline]='3.20'
     [stable]='3.19'
 )