According to the requirements characteristics at different stages of generalized product design process and acceleration of the transformation from conceptual design to detailed design, a method of conceptual design push of 3D CAD model of products based on sketch was proposed. First of all, according to the conceptual design requirements, a three-view sketch was drawn by using a hand drawing board based on CAD geometric modeling platform. Then, feature information was extracted from hand-drawn three-view sketch and three-view projection diagram of CAD model projection in model library, and the 2.5D spherical harmonic descriptor was used to represent the sketch feature information. Finally, Euclidean distance was used to calculate the distance of the graph feature vectors obtained by spherical harmonic transformation to realize the similarity evaluation between models and verify the algorithm in the agricultural machinery equipment model database. The experimental results showed that the method can effectively help users visualize the query intention quickly, explore the 3D model which was most consistent with the intention of product conceptual design stage, and push the similar design resources to designers, so as to reference, inspire and expand the design thinking and realize the rapid response of product conceptual design.