diff --git a/src/main/java/run/halo/app/service/TagService.java b/src/main/java/run/halo/app/service/TagService.java
index 1805d87abd..14e88d7c63 100644
--- a/src/main/java/run/halo/app/service/TagService.java
+++ b/src/main/java/run/halo/app/service/TagService.java
@@ -31,7 +31,7 @@ public interface TagService extends CrudService<Tag, Integer> {
      * @param slug slug
      * @return tag
      */
-    @NonNull
+    @Nullable
     Tag getBySlug(@NonNull String slug);
 
     /**
diff --git a/src/main/java/run/halo/app/service/impl/PostServiceImpl.java b/src/main/java/run/halo/app/service/impl/PostServiceImpl.java
index 4eeb351a74..f432f0b508 100644
--- a/src/main/java/run/halo/app/service/impl/PostServiceImpl.java
+++ b/src/main/java/run/halo/app/service/impl/PostServiceImpl.java
@@ -412,10 +412,14 @@ public PostDetailVO importMarkdown(String markdown, String filename) {
                                 tagName = StringUtils.strip(tagName, "\"");
                                 tagName = StringUtils.strip(tagName, "\'");
                                 tag = tagService.getByName(tagName);
+                                String slug = SlugUtils.slug(tagName);
+                                if (null == tag) {
+                                    tag = tagService.getBySlug(slug);
+                                }
                                 if (null == tag) {
                                     tag = new Tag();
                                     tag.setName(tagName);
-                                    tag.setSlug(SlugUtils.slug(tagName));
+                                    tag.setSlug(slug);
                                     tag = tagService.create(tag);
                                 }
                                 tagIds.add(tag.getId());
diff --git a/src/main/java/run/halo/app/utils/MarkdownUtils.java b/src/main/java/run/halo/app/utils/MarkdownUtils.java
index 349a338b8b..78389f6c79 100644
--- a/src/main/java/run/halo/app/utils/MarkdownUtils.java
+++ b/src/main/java/run/halo/app/utils/MarkdownUtils.java
@@ -71,7 +71,7 @@ public class MarkdownUtils {
     private static final Parser PARSER = Parser.builder(OPTIONS).build();
 
     private static final HtmlRenderer RENDERER = HtmlRenderer.builder(OPTIONS).build();
-    private static final Pattern FRONT_MATTER = Pattern.compile("^---[\\s\\S]*?---");
+    private static final Pattern FRONT_MATTER = Pattern.compile("^(---)?[\\s\\S]*?---");
 
     //    /**
     //     * Render html document to markdown document.
@@ -136,6 +136,9 @@ public static Map<String, List<String>> getFrontMatter(String markdown) {
                 return row;
             }
         }).collect(Collectors.joining("\n"));
+        if (!markdown.startsWith("---\n")) {
+            markdown = "---\n" + markdown;
+        }
         AbstractYamlFrontMatterVisitor visitor = new AbstractYamlFrontMatterVisitor();
         Node document = PARSER.parse(markdown);
         visitor.visit(document);
diff --git a/src/test/java/run/halo/app/utils/MarkdownUtilsTest.java b/src/test/java/run/halo/app/utils/MarkdownUtilsTest.java
index c42533be19..fb2ffde163 100644
--- a/src/test/java/run/halo/app/utils/MarkdownUtilsTest.java
+++ b/src/test/java/run/halo/app/utils/MarkdownUtilsTest.java
@@ -3,6 +3,8 @@
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
+import java.util.List;
+import java.util.Map;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.commons.lang3.StringUtils;
 import org.junit.jupiter.api.Test;
@@ -33,6 +35,15 @@ void removeFrontMatter() {
             + "---"
             + "test---";
         assertEquals("test---", MarkdownUtils.removeFrontMatter(markdown));
+
+        markdown = "title: \"test remove\"\n"
+            + "test---";
+        assertEquals("", MarkdownUtils.removeFrontMatter(markdown));
+
+        markdown = "title: \"test remove\"\n"
+            + "---"
+            + "test---";
+        assertEquals("test---", MarkdownUtils.removeFrontMatter(markdown));
     }
 
     @Test
@@ -70,4 +81,18 @@ void footNotesTest() {
             + "</section>\n";
         assertTrue(StringUtils.equals(s2Expected, s2));
     }
+
+    @Test
+    void getFrontMatter() {
+        String markdown = "---\n"
+            + "title: \"test remove\"\n"
+            + "---";
+        Map<String, List<String>> frontMatter = MarkdownUtils.getFrontMatter(markdown);
+        assertEquals("\"test remove\"", frontMatter.get("title").get(0));
+
+        markdown = "title: \"test remove\"\n"
+            + "---";
+        frontMatter = MarkdownUtils.getFrontMatter(markdown);
+        assertEquals("\"test remove\"", frontMatter.get("title").get(0));
+    }
 }
\ No newline at end of file