diff --git a/swoole/7.4/Dockerfile b/swoole/7.4/Dockerfile
index 6d94722..90e5817 100644
--- a/swoole/7.4/Dockerfile
+++ b/swoole/7.4/Dockerfile
@@ -34,6 +34,8 @@ RUN set -ex \
     && rm -rf /var/cache/apk/* /tmp/* /usr/share/man \
     && echo -e "\033[42;37m Build Completed :).\033[0m\n"
 
+ENV LD_PRELOAD /usr/lib/preloadable_libiconv.so php
+
 WORKDIR /srv/www
 
 EXPOSE 9501
\ No newline at end of file
diff --git a/swoole/8.1/Dockerfile b/swoole/8.1/Dockerfile
index b741561..be49610 100644
--- a/swoole/8.1/Dockerfile
+++ b/swoole/8.1/Dockerfile
@@ -21,7 +21,7 @@ RUN set -ex \
     && php -v \
     && php -m \
     && php --ri swoole \
-    && apk add --no-cache --repository https://mirrors.aliyun.com/alpine/edge/testing gnu-libiconv  \
+    && apk add --no-cache --repository https://mirrors.aliyun.com/alpine/edge/testing gnu-libiconv \
     #  ---------- some config ----------
     && cd /etc/php81 \
     # - config PHP
@@ -34,6 +34,8 @@ RUN set -ex \
     && rm -rf /var/cache/apk/* /tmp/* /usr/share/man \
     && echo -e "\033[42;37m Build Completed :).\033[0m\n"
 
+ENV LD_PRELOAD /usr/lib/preloadable_libiconv.so php
+
 WORKDIR /srv/www
 
 EXPOSE 9501
\ No newline at end of file
diff --git a/swoole/8.2/Dockerfile b/swoole/8.2/Dockerfile
index 8572d34..5cf6701 100644
--- a/swoole/8.2/Dockerfile
+++ b/swoole/8.2/Dockerfile
@@ -34,6 +34,8 @@ RUN set -ex \
     && rm -rf /var/cache/apk/* /tmp/* /usr/share/man \
     && echo -e "\033[42;37m Build Completed :).\033[0m\n"
 
+ENV LD_PRELOAD /usr/lib/preloadable_libiconv.so php
+
 WORKDIR /srv/www
 
 EXPOSE 9501
\ No newline at end of file
diff --git a/swoole/8.3/Dockerfile b/swoole/8.3/Dockerfile
index 6fcd006..b7147da 100644
--- a/swoole/8.3/Dockerfile
+++ b/swoole/8.3/Dockerfile
@@ -34,6 +34,8 @@ RUN set -ex \
     && rm -rf /var/cache/apk/* /tmp/* /usr/share/man \
     && echo -e "\033[42;37m Build Completed :).\033[0m\n"
 
+ENV LD_PRELOAD /usr/lib/preloadable_libiconv.so php
+
 WORKDIR /srv/www
 
 EXPOSE 9501
\ No newline at end of file