MeshPad is an innovative generative design tool that focuses on creating and editing 3D mesh models from sketch input. It achieves complex mesh generation and editing through simple sketch operations, providing users with an intuitive and efficient 3D modeling experience. The tool is based on triangular sequence mesh representation and utilizes a large Transformer model to implement mesh addition and deletion operations. Simultaneously, a vertex alignment prediction strategy significantly reduces computational cost, making each edit take only a few seconds. MeshPad surpasses existing sketch-conditioned mesh generation methods in mesh quality and has received high user recognition in perceptual evaluation. It is primarily aimed at designers, artists, and users who need to quickly perform 3D modeling, helping them create artistic designs in a more intuitive way.