The invention discloses a wall thickness homogenization method adopting isothermal stamping for a titanium alloy thick-wall spherical shell. Through divisional design on friction coefficients of a male die and a to-be-formed plate, the male die and pull rings are heated separately so that a temperature gradient is formed, the wall thickness homogenization of the titanium alloy thick-wall sphericalshell is ensured, the spherical bottom reduction rate is reduced from 50% in conventional forming to below 15%, the overall wall thickness fluctuation of a housing does not exceeds 30% of the wall thickness of a blank and the size is stable. Since the reduction of the spherical bottom is inhibited effectively, the extent of damage of the mechanical property at the spherical bottom is reduced substantially, the overall mechanical property of the titanium alloy thick-wall spherical shell is better, the titanium alloy thick-wall spherical shell is particularly applicable to development and production of a TA7 low-temperature titanium alloy gas cylinder product for a carrier rocket, and is also applicable to the development and production of titanium alloys in other fields and other trademarks and the like products, and the wall thickness homogenization method is very practical.