diff --git a/models/issues/review.go b/models/issues/review.go
index 5835900801..ba12876dc5 100644
--- a/models/issues/review.go
+++ b/models/issues/review.go
@@ -626,17 +626,7 @@ func InsertReviews(reviews []*Review) error {
 			return err
 		}
 
-		if _, err := sess.NoAutoTime().Insert(&Comment{
-			Type:             CommentTypeReview,
-			Content:          review.Content,
-			PosterID:         review.ReviewerID,
-			OriginalAuthor:   review.OriginalAuthor,
-			OriginalAuthorID: review.OriginalAuthorID,
-			IssueID:          review.IssueID,
-			ReviewID:         review.ID,
-			CreatedUnix:      review.CreatedUnix,
-			UpdatedUnix:      review.UpdatedUnix,
-		}); err != nil {
+		if _, err := sess.NoAutoTime().Insert(generateCommentFromReview(review)); err != nil {
 			return err
 		}
 
@@ -654,6 +644,112 @@ func InsertReviews(reviews []*Review) error {
 	return committer.Commit()
 }
 
+// UpsertReviews inserts new reviews and updates existing ones.
+// This function is used for syncing from the pull mirror.
+func UpsertReviews(reviews []*Review) error {
+	ctx, committer, err := db.TxContext()
+	if err != nil {
+		return err
+	}
+	defer committer.Close()
+	sess := db.GetEngine(ctx)
+
+	for _, review := range reviews {
+		exists, err := sess.Where("issue_id = ? AND created_unix", review.IssueID, review.CreatedUnix).Exist(&Review{})
+		if err != nil {
+			return err
+		}
+
+		if !exists {
+			if _, err := sess.NoAutoTime().Insert(review); err != nil {
+				return err
+			}
+
+			if _, err := sess.NoAutoTime().Insert(generateCommentFromReview(review)); err != nil {
+				return err
+			}
+
+			for _, c := range review.Comments {
+				c.ReviewID = review.ID
+			}
+
+			if len(review.Comments) > 0 {
+				if _, err := sess.NoAutoTime().Insert(review.Comments); err != nil {
+					return err
+				}
+			}
+		} else {
+			if _, err = sess.NoAutoTime().Where("issue_id = ? AND created_unix", review.IssueID, review.CreatedUnix).Update(review); err != nil {
+				return err
+			}
+
+			// Get id of the review
+			if err = sess.NoAutoTime().Where("issue_id = ? AND created_unix", review.IssueID, review.CreatedUnix).Find(review); err != nil {
+				return err
+			}
+
+			comment := generateCommentFromReview(review)
+			exists, err := existsCommentByReviewIDAndCreatedUnix(sess, comment)
+			if err != nil {
+				return err
+			}
+
+			if !exists {
+				if _, err := sess.NoAutoTime().Insert(comment); err != nil {
+					return err
+				}
+			} else {
+				if _, err := sess.NoAutoTime().Where("review_id = ? AND created_unix = ?", review.ID, comment.CreatedUnix).Update(comment); err != nil {
+					return err
+				}
+			}
+
+			for _, c := range review.Comments {
+				c.ReviewID = review.ID
+			}
+
+			if len(review.Comments) > 0 {
+				for _, comment := range review.Comments {
+					exists, err := existsCommentByReviewIDAndCreatedUnix(sess, comment)
+					if err != nil {
+						return err
+					}
+
+					if !exists {
+						if _, err := sess.NoAutoTime().Insert(comment); err != nil {
+							return err
+						}
+					} else {
+						if _, err := sess.NoAutoTime().Where("review_id = ? AND created_unix = ?", review.ID, comment.CreatedUnix).Update(comment); err != nil {
+							return err
+						}
+					}
+				}
+			}
+		}
+	}
+
+	return committer.Commit()
+}
+
+func existsCommentByReviewIDAndCreatedUnix(sess db.Engine, comment *Comment) (bool, error) {
+	return sess.Where("review_id = ? AND created_unix = ?", comment.ReviewID, comment.CreatedUnix).Exist(&Comment{})
+}
+
+func generateCommentFromReview(review *Review) *Comment {
+	return &Comment{
+		Type:             CommentTypeReview,
+		Content:          review.Content,
+		PosterID:         review.ReviewerID,
+		OriginalAuthor:   review.OriginalAuthor,
+		OriginalAuthorID: review.OriginalAuthorID,
+		IssueID:          review.IssueID,
+		ReviewID:         review.ID,
+		CreatedUnix:      review.CreatedUnix,
+		UpdatedUnix:      review.UpdatedUnix,
+	}
+}
+
 // AddReviewRequest add a review request from one reviewer
 func AddReviewRequest(issue *Issue, reviewer, doer *user_model.User) (*Comment, error) {
 	ctx, committer, err := db.TxContext()
diff --git a/services/migrations/gitea_uploader.go b/services/migrations/gitea_uploader.go
index f23a8a1439..559240a80a 100644
--- a/services/migrations/gitea_uploader.go
+++ b/services/migrations/gitea_uploader.go
@@ -747,14 +747,13 @@ func convertReviewState(state string) issues_model.ReviewType {
 	}
 }
 
-// CreateReviews create pull request reviews of currently migrated issues
-func (g *GiteaLocalUploader) CreateReviews(reviews ...*base.Review) error {
+func (g *GiteaLocalUploader) prepareReviews(reviews ...*base.Review) ([]*issues_model.Review, error) {
 	cms := make([]*issues_model.Review, 0, len(reviews))
 	for _, review := range reviews {
 		var issue *issues_model.Issue
 		issue, ok := g.issues[review.IssueIndex]
 		if !ok {
-			return fmt.Errorf("review references non existent IssueIndex %d", review.IssueIndex)
+			return nil, fmt.Errorf("review references non existent IssueIndex %d", review.IssueIndex)
 		}
 		if review.CreatedAt.IsZero() {
 			review.CreatedAt = time.Unix(int64(issue.CreatedUnix), 0)
@@ -770,7 +769,7 @@ func (g *GiteaLocalUploader) CreateReviews(reviews ...*base.Review) error {
 		}
 
 		if err := g.remapUser(review, &cm); err != nil {
-			return err
+			return nil, err
 		}
 
 		// get pr
@@ -779,7 +778,7 @@ func (g *GiteaLocalUploader) CreateReviews(reviews ...*base.Review) error {
 			var err error
 			pr, err = issues_model.GetPullRequestByIssueIDWithNoAttributes(issue.ID)
 			if err != nil {
-				return err
+				return nil, err
 			}
 			g.prCache[issue.ID] = pr
 		}
@@ -833,7 +832,7 @@ func (g *GiteaLocalUploader) CreateReviews(reviews ...*base.Review) error {
 			}
 
 			if err := g.remapUser(review, &c); err != nil {
-				return err
+				return nil, err
 			}
 
 			cm.Comments = append(cm.Comments, &c)
@@ -842,6 +841,16 @@ func (g *GiteaLocalUploader) CreateReviews(reviews ...*base.Review) error {
 		cms = append(cms, &cm)
 	}
 
+	return cms, nil
+}
+
+// CreateReviews create pull request reviews of currently migrated issues
+func (g *GiteaLocalUploader) CreateReviews(reviews ...*base.Review) error {
+	cms, err := g.prepareReviews(reviews...)
+	if err != nil {
+		return err
+	}
+
 	return issues_model.InsertReviews(cms)
 }
 
@@ -932,7 +941,12 @@ func (g *GiteaLocalUploader) PatchPullRequests(prs ...*base.PullRequest) error {
 }
 
 func (g *GiteaLocalUploader) PatchReviews(reviews ...*base.Review) error {
-	return nil
+	cms, err := g.prepareReviews(reviews...)
+	if err != nil {
+		return err
+	}
+
+	return issues_model.UpsertReviews(cms)
 }
 
 // Rollback when migrating failed, this will rollback all the changes.