diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6b34f7b..529ab4d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,7 @@
 
 ## Changes since v3.2.0
 
+- [#169](https://github.com/pusher/outh2_proxy/pull/169) Update Alpine to 3.9 (@kskewes)
 - [#148](https://github.com/pusher/outh2_proxy/pull/148) Implement SessionStore interface within proxy (@JoelSpeed)
 - [#147](https://github.com/pusher/outh2_proxy/pull/147) Add SessionStore interfaces and initial implementation (@JoelSpeed)
   - Allows for multiple different session storage implementations including client and server side
diff --git a/Dockerfile b/Dockerfile
index a734e27..f6649a9 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -20,7 +20,7 @@ RUN dep ensure --vendor-only
 RUN ./configure && make build && touch jwt_signing_key.pem
 
 # Copy binary to alpine
-FROM alpine:3.8
+FROM alpine:3.9
 COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
 COPY --from=builder /go/src/github.com/pusher/oauth2_proxy/oauth2_proxy /bin/oauth2_proxy
 COPY --from=builder /go/src/github.com/pusher/oauth2_proxy/jwt_signing_key.pem /etc/ssl/private/jwt_signing_key.pem
diff --git a/Dockerfile.arm64 b/Dockerfile.arm64
index 7fdb2f8..7f011ba 100644
--- a/Dockerfile.arm64
+++ b/Dockerfile.arm64
@@ -20,7 +20,7 @@ RUN dep ensure --vendor-only
 RUN ./configure && GOARCH=arm64 make build && touch jwt_signing_key.pem
 
 # Copy binary to alpine
-FROM arm64v8/alpine:3.8
+FROM arm64v8/alpine:3.9
 COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
 COPY --from=builder /go/src/github.com/pusher/oauth2_proxy/oauth2_proxy /bin/oauth2_proxy
 COPY --from=builder /go/src/github.com/pusher/oauth2_proxy/jwt_signing_key.pem /etc/ssl/private/jwt_signing_key.pem
diff --git a/Dockerfile.armv6 b/Dockerfile.armv6
index dfe4fe2..e2c57b9 100644
--- a/Dockerfile.armv6
+++ b/Dockerfile.armv6
@@ -20,7 +20,7 @@ RUN dep ensure --vendor-only
 RUN ./configure && GOARCH=arm GOARM=6 make build && touch jwt_signing_key.pem
 
 # Copy binary to alpine
-FROM arm32v6/alpine:3.8
+FROM arm32v6/alpine:3.9
 COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
 COPY --from=builder /go/src/github.com/pusher/oauth2_proxy/oauth2_proxy /bin/oauth2_proxy
 COPY --from=builder /go/src/github.com/pusher/oauth2_proxy/jwt_signing_key.pem /etc/ssl/private/jwt_signing_key.pem