In this paper, the development and prospect of tower-shaped solar thermal power generation technology are briefly introduced, and the importance of production quality of molten salt storage tank in tower thermal power storage system is proposed. The production technology and construction process of molten salt storage tank are described in detail, and the key technology and multiple problems affecting quality are analysed. Aiming at the problem of fillet weld deformation, this paper proposes a new anti-deformation tooling and welding operation technology. At last, this paper presents a construction technology method and a solution to improve the welding quality of molten salt storage tank, which can effectively solve the problem that the bottom plate of molten salt storage tank is out of standard due to welding.