The invention discloses water tightness test equipment adopting a cylindrical surface design. The water tightness test equipment comprises a pull cable and a seal barrel; colored water is arranged inthe seal barrel; the pull cable penetrates through the seal barrel; one end of the pull cable is fixedly arranged; a traction device is arranged at the other end of the pull cable; the traction devicecomprises a transverse jack, a deflection base plate and a pressure-bearing base plate; the pressure-bearing base plate is fixedly arranged at a barrel opening of the seal barrel; the deflection baseplate is arranged on the pressure-bearing base plate; the pull cable penetrates through the pressure-bearing base plate and the deflection base plate; the contact surface of the deflection base plateand the pressure-bearing base plate is a cylindrical surface; the transverse jack is also arranged on the pressure-bearing base plate; the transverse jack faces to the deflection base plate; the transverse jack is connected with the deflection base plate; and the transverse jack can drive the deflection base plate. Compared with a traditional design in which a plane is adopted as a bonding surface, the water tightness test equipment adopting the cylindrical surface design has the advantages that restoring force is larger, so that an output of the transverse jack is smaller, the manufacturingdifficulty and the manufacturing degree are reduced, and the economical efficiency is improved.