A foldable miter saw includes a base unit, a worktable, and a cutting unit adjustable between a working position where the saw blade of the cutting unit and the worktable define a contained angle within 90°˜45° and a folded position where one end face of the saw blade is disposed in proximity to the working surface and one guiding member and one sliding coupling component of the worktable are disposed in proximity to a working surface of the worktable, significantly reducing the dimension of the foldable miter saw and facilitating storage and packaging.