diff --git a/storage/sealer/fsutil/filesize_unix.go b/storage/sealer/fsutil/filesize_unix.go
index 9c7f04ace..3d80e0b8a 100644
--- a/storage/sealer/fsutil/filesize_unix.go
+++ b/storage/sealer/fsutil/filesize_unix.go
@@ -1,3 +1,6 @@
+//go:build !windows
+// +build !windows
+
 package fsutil
 
 import (
diff --git a/storage/sealer/fsutil/filesize_windows.go b/storage/sealer/fsutil/filesize_windows.go
new file mode 100644
index 000000000..aeef50473
--- /dev/null
+++ b/storage/sealer/fsutil/filesize_windows.go
@@ -0,0 +1,16 @@
+package fsutil
+
+import (
+	"fmt"
+)
+
+type SizeInfo struct {
+	OnDisk int64
+}
+
+// FileSize returns bytes used by a file or directory on disk
+// NOTE: We care about the allocated bytes, not file or directory size
+// This is not currently supported on Windows, but at least other lotus can components can build on Windows now
+func FileSize(path string) (SizeInfo, error) {
+	return SizeInfo{0}, fmt.Errorf("unsupported")
+}