A method of producing a high-pressure tank including a liner and a reinforcement layer made of fiber-reinforced resin includes a process of forming at least a domed member included in the reinforcement layer. The process includes placing first fiber bundles to form a part of a protruding portion and a part of a domed main body, and placing second fiber bundles to cover the first fiber bundles. The first fiber bundles are placed, such that a fiber direction of the first fiber bundles in the protruding portion follows an axial direction of the protruding portion, and resin with which the fiber bundles are impregnated is solidified while the first fiber bundles are being placed. The second fiber bundles are placed, such that the fiber direction of the second fiber bundles intersects with the fiber direction of the first fiber bundles.