With the rapid development of digital technology, virtual painting, as an emerging design tool, gradually plays an important role in the field of product design. The purpose of this paper is to explore the impact of virtual painting based on computer simulation on innovative thinking of product design. By analysing the concept and development of virtual painting, combined with the application cases of computer simulation technology, the study shows that virtual painting not only enhances the creativity and flexibility of designers, but also provides a richer means of expression for product design. In addition, the paper explores the advantages of virtual drawing in the design process and its impact on traditional drawing methods, and finally looks at the potential and challenges of applying virtual drawing in product design in the future. The findings provide important theoretical basis and practical guidance for designers and related industries.