Abstract: To solve the problem that the existing CAD system is difficult to match the corresponding parts accurately through the freehand sketch in the conceptual design,a recognition model(VGG-CapsNet)for freehand sketch of part is proposed,which combining the pre-trained network(VGG)and capsule network(CapsNet).Five designers are recruited to sketch parts,and build 23 kinds of freehand sketch of parts in-cluding standard parts and non-standard parts.The between-group experiment and within-group experiment are designed,and then the recognition models of VGG-CapsNet are constructed respectively.The recogni-tion results of the VGG-CapsNet models are compared with the rVGG-13 models and the rCNN-13 models.The experimental results show that the mean accuracy of VGG-CapsNet model is higher than the other two models,which provides technical support for the retrieval and reuse of part design knowledge.