The work aims to solve the current problems of high requirements for designers, limited design thinking and long design cycles in product design expression. A method for fast generation of product renderings from sketches based on StyleGAN was proposed. The image deformation techniques was adopted to generate real product renderings from product sketches of different degrees. The method can effectively meet the creative needs of designers and generate high-quality product design solutions for users who have no basic drawing skills. Applying the StyleGAN model based on deep learning in sketches to generate real product renderings can quickly and efficiently complete the product design expression process. It provides a reference framework based on deep learning technology for product design expression and is an innovative exploration of traditional product design in the era of artificial intelligence.