The design of 700-bar composite tanks considering the safety factor imposes resistance to a bursting pressure greater than 1645 bars remains difficult which leads to the addition of carbon fibers. On the other hand, the specifications in terms of mass storage capacity and cost require the quantity of this same fiber to be limited. Thus, the optimal sizing of the composite remains one of the major challenges in the development of 700-bar tanks. This study is focused on an optimum design of dome contours for 700 bar hydrogen tank type IV considering the geometrical limitations, winding condition, and the feasible direction. The study is centered on the composite part and is separated into two parts: a study of the manufacturing process (filament winding) in its fundamental aspects and a structural calculation under HyperWorks to check the mechanical strength of the composite layers and optimize their stacking and the number to ensure the holding while minimizing the mass and therefore the cost of the tank.