Abstract: Feature recognition and shape classification of ship hull plates have important significance for the optimal selection of processing parameters of shell plates. A feature recognition method was proposed in this paper, based on curved surface decomposition. The method firstly decomposed the curved surfaces of shell plates into transverse bending surfaces, longitudinal bending surfaces and torsional bending surfaces. Then, the features of decomposed bending surfaces were analyzed. Characteristics and classification rules of four kinds of simple plate types were summarized according to the plate type classification experience of experts. The experimental results show that the method can accurately obtain the characteristic parameters and type of the hull plates, and support the optimal selection of processing parameters of shell plates.