diff --git a/internal/executor/gitundo.go b/internal/executor/gitundo.go
new file mode 100644
index 0000000..101db3f
--- /dev/null
+++ b/internal/executor/gitundo.go
@@ -0,0 +1,94 @@
+package executor
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"strings"
+)
+
+// gitUndoOptions are the parsed arguments of `kopsc git undo`.
+type gitUndoOptions struct {
+	Hard bool
+}
+
+// runGitUndo undoes the last commit.
+func runGitUndo(ctx context.Context, req BuiltinRequest) error {
+	return runGitUndoWith(ctx, req, execGitRunner{})
+}
+
+func runGitUndoWith(ctx context.Context, req BuiltinRequest, runner gitRunner) error {
+	opts, confirmed, err := parseGitUndoArgs(req.Args)
+	if err != nil {
+		return err
+	}
+	confirmed = confirmed || req.Confirmed
+
+	// Get the last commit info
+	out, _, err := runner.Run(ctx, "log", "-1", "--format=%h %s")
+	if err != nil {
+		return fmt.Errorf("获取提交信息失败: %w", err)
+	}
+
+	lastCommit := strings.TrimSpace(out)
+	if lastCommit == "" {
+		return errors.New("没有提交可以撤销")
+	}
+
+	// Show preview
+	fmt.Fprintf(req.Stdout, "撤销最后一次提交\n\n")
+	fmt.Fprintf(req.Stdout, "提交: %s\n", lastCommit)
+
+	if opts.Hard {
+		fmt.Fprintf(req.Stdout, "模式: 完全丢弃改动（--hard）\n")
+	} else {
+		fmt.Fprintf(req.Stdout, "模式: 保留改动到暂存区（--soft）\n")
+	}
+
+	if !confirmed {
+		fmt.Fprintf(req.Stdout, "\n")
+		if opts.Hard {
+			fmt.Fprintf(req.Stdout, "⚠️  这将永久丢弃最后一次提交的改动！加 --yes 确认执行。\n")
+		} else {
+			fmt.Fprintf(req.Stdout, "撤销后改动会保留在暂存区，加 --yes 执行。\n")
+		}
+		return &ExitError{Code: 2, Err: errors.New("需要确认")}
+	}
+
+	// Execute undo
+	resetArg := "--soft"
+	if opts.Hard {
+		resetArg = "--hard"
+	}
+
+	if _, stderr, err := runner.Run(ctx, "reset", resetArg, "HEAD~1"); err != nil {
+		return fmt.Errorf("撤销失败: %w\n%s", err, stderr)
+	}
+
+	if opts.Hard {
+		fmt.Fprintf(req.Stdout, "\n✓ 已撤销提交并丢弃改动\n")
+	} else {
+		fmt.Fprintf(req.Stdout, "\n✓ 已撤销提交，改动保留在暂存区\n")
+	}
+	return nil
+}
+
+func parseGitUndoArgs(args []string) (gitUndoOptions, bool, error) {
+	var opts gitUndoOptions
+	var confirmed bool
+
+	for _, arg := range args {
+		switch arg {
+		case "--yes", "-y":
+			confirmed = true
+		case "--hard":
+			opts.Hard = true
+		default:
+			if strings.HasPrefix(arg, "-") {
+				return opts, false, fmt.Errorf("未知选项 %q", arg)
+			}
+		}
+	}
+
+	return opts, confirmed, nil
+}