Abstract In order to manufacture eligible large-scale composite container, this paper formulates a design and manufacturing scheme for the forming mould of a composite container. The composite container is a large long-axis product, the foming mould of which would appear serious deflection and bear large demoulding force. The main mould structure adopts the combination structure of full-length steel pipe, web plates along circle direction, stiffeners along circle direction and skins. For the designed forming mould, the three-dimensional network structure made up by the seamless steel pipe, skeleton and skins effectively guarantees the rigidity; the draft surface and gradual fillet design significantly decreases the demoulding force; thicker steel plates were used in the ejection end to improve its reliability in the demoulding process. The simulation results show that the maximum stress value and deformation value are respectively 42.9MPa and 0.51mm in the simply supported condition, and the maximum stress values and deformation values are respectively 188.6MPa and 0.5mm in demoulding condition. According to the mould structure, the processing route of separately assembly welding and integrated assembling for the forming mould was formulated and the forming mould was manufactured. The simulation and practical use results show that the designed forming mould can meet the production needs of the large-scale composite container.