The invention relates to a ratchet wrench comprising a prolonging handle which comprises two first boards and a second board, wherein both first board are disposed on the upper and lower side of the second board, a ring portion is disposed on at least one end of the both ends of the first boards, a space is formed between the upper and the lower boards; a ratchet is rotatably accommodated in the space, while protrudes outside a through-hole, ratchet teeth are disposed around the ratchet. A jack piece is provided between the prolonging handle and the ratchet, an elastic piece is provided between the jack piece and the prolonging handle. The jack piece is pressed by the elastic piece, and the jack piece engages with ratchet teeth of the ratchet, wherein the ratchet is capable of arbitrarilyrotating in the space of the first boards to an angle and direction convenient for user to use.