diff --git a/application/src/main/java/run/halo/app/core/attachment/endpoint/LocalAttachmentUploadHandler.java b/application/src/main/java/run/halo/app/core/attachment/endpoint/LocalAttachmentUploadHandler.java
index 3de4453bf..837ed57c1 100644
--- a/application/src/main/java/run/halo/app/core/attachment/endpoint/LocalAttachmentUploadHandler.java
+++ b/application/src/main/java/run/halo/app/core/attachment/endpoint/LocalAttachmentUploadHandler.java
@@ -283,18 +283,27 @@ class LocalAttachmentUploadHandler implements AttachmentHandler {
         return Mono.just(doGetThumbnailLinks(attachment));
     }
 
-    private Optional<URI> doGetPermalink(Attachment attachment) {
+    protected Optional<URI> doGetPermalink(Attachment attachment) {
         var annotations = attachment.getMetadata().getAnnotations();
         if (annotations == null
             || !annotations.containsKey(Constant.URI_ANNO_KEY)) {
             return Optional.empty();
         }
         var uriStr = annotations.get(Constant.URI_ANNO_KEY);
-        var uri = UriComponentsBuilder.fromUri(externalUrl.get())
-            // The URI has been encoded before, so there is no need to encode it again.
-            .path(uriStr)
-            .build(true)
-            .toUri();
+        URI uri;
+        try {
+            uri = UriComponentsBuilder.fromUri(externalUrl.get())
+                // The URI has been encoded before, so there is no need to encode it again.
+                .path(uriStr)
+                .build(true)
+                .toUri();
+        } catch (IllegalArgumentException e) {
+            // The URI may not be encoded, so we need to build with encoding.
+            uri = UriComponentsBuilder.fromUri(externalUrl.get())
+                .path(uriStr)
+                .build()
+                .toUri();
+        }
         return Optional.of(uri);
     }
 
diff --git a/application/src/test/java/run/halo/app/core/attachment/endpoint/LocalAttachmentUploadHandlerTest.java b/application/src/test/java/run/halo/app/core/attachment/endpoint/LocalAttachmentUploadHandlerTest.java
index fe0bce2f9..b343c0b4e 100644
--- a/application/src/test/java/run/halo/app/core/attachment/endpoint/LocalAttachmentUploadHandlerTest.java
+++ b/application/src/test/java/run/halo/app/core/attachment/endpoint/LocalAttachmentUploadHandlerTest.java
@@ -17,6 +17,7 @@ import java.util.Map;
 import java.util.function.Consumer;
 import java.util.stream.Stream;
 import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.junit.jupiter.api.io.TempDir;
 import org.junit.jupiter.params.ParameterizedTest;
@@ -32,9 +33,11 @@ import reactor.core.publisher.Flux;
 import reactor.test.StepVerifier;
 import run.halo.app.core.attachment.AttachmentRootGetter;
 import run.halo.app.core.extension.attachment.Attachment;
+import run.halo.app.core.extension.attachment.Constant;
 import run.halo.app.core.extension.attachment.Policy;
 import run.halo.app.core.extension.attachment.endpoint.UploadOption;
 import run.halo.app.extension.ConfigMap;
+import run.halo.app.extension.Metadata;
 import run.halo.app.infra.ExternalUrlSupplier;
 
 @ExtendWith(MockitoExtension.class)
@@ -210,4 +213,16 @@ class LocalAttachmentUploadHandlerTest {
 
     }
 
+    @Test
+    void shouldGetPermalinkWhenUriContainsIllegalChars() {
+        var attachment = new Attachment();
+        attachment.setMetadata(new Metadata());
+        attachment.getMetadata().setAnnotations(Map.of(
+            Constant.URI_ANNO_KEY, "/path/with space.png"
+        ));
+        var permalink = uploadHandler.doGetPermalink(attachment);
+        assertTrue(permalink.isPresent());
+        assertEquals("/path/with%20space.png", permalink.get().toASCIIString());
+    }
+
 }
\ No newline at end of file