The invention provides a tool and a forming process for forming hook aircraft skin parts. The tool comprises a left bracket and a right bracket, wherein a rolling shaft is arranged on the left bracketand the right bracket; the two ends of the rolling shaft are fixed with the left bracket and the right bracket through a left end cover and a right end cover; and a transverse key and a vertical keyare separately arranged inside the left bracket and the right bracket. The forming process comprises the following steps of: fixing and connecting the left bracket and the right bracket to a mould through the keys, blanking, pre-bending plates, mounting the plates, clamping the plates, regulating a jaw angle of a tong head of stretching equipment, stretching the plates by a left stretching cylinder and a right stretching cylinder of the stretching equipment, cutting side parts of the plates, and the like. The tool and the forming process have the advantages that: integrity of the skin parts can be guaranteed, quantity of cut skin parts is reduced, and integral strength and rigidity of the skin parts are improved. The process of the hook aircraft skin parts further can be simplified, processing difficulty further can be reduced, production efficiency and advanced manufacturing level of plate rib parts in the plastic processing filed are effectively improved, and the production cost is greatly reduced.