A spinning forming method comprising: a first forming step (S203, S204; S503, S504) of forming a first level-changing portion by, while rotating a plate fixed to a main shaft, causing a processing tool to contact a first main surface of the plate, the first level-changing portion extending from the first main surface toward a second main surface opposite to the first main surface; and a second forming step (S205; S508, S509) of forming a second level-changing portion by, while rotating the plate fixed to the main shaft, causing the processing tool to contact the second main surface of the plate at an outer peripheral side of the first level-changing portion, the second level-changing portion extending in an opposite direction to the first level-changing portion; characterised in that: in the first forming step, a heater provided at an opposite side from the processing tool across the plate locally heats a position of the second main surface of the plate, the position being located on a circumference defined by a position (r) of the plate at which the processing tool contacts the plate; and in the second forming step, the heater provided at the opposite side from the processing tool across the plate locally heats a position of the first main surface of the plate, the position being located on the circumference defined by the position (r) of the plate at which the processing tool contacts the plate. a first forming step (S203, S204; S503, S504) of forming a first level-changing portion by, while rotating a plate fixed to a main shaft, causing a processing tool to contact a first main surface of the plate, the first level-changing portion extending from the first main surface toward a second main surface opposite to the first main surface; and a second forming step (S205; S508, S509) of forming a second level-changing portion by, while rotating the plate fixed to the main shaft, causing the processing tool to contact the second main surface of the plate at an outer peripheral side of the first level-changing portion, the second level-changing portion extending in an opposite direction to the first level-changing portion; characterised in that: in the first forming step, a heater provided at an opposite side from the processing tool across the plate locally heats a position of the second main surface of the plate, the position being located on a circumference defined by a position (r) of the plate at which the processing tool contacts the plate; and in the second forming step, the heater provided at the opposite side from the processing tool across the plate locally heats a position of the first main surface of the plate, the position being located on the circumference defined by the position (r) of the plate at which the processing tool contacts the plate. in the first forming step, a heater provided at an opposite side from the processing tool across the plate locally heats a position of the second main surface of the plate, the position being located on a circumference defined by a position (r) of the plate at which the processing tool contacts the plate; and in the second forming step, the heater provided at the opposite side from the processing tool across the plate locally heats a position of the first main surface of the plate, the position being located on the circumference defined by the position (r) of the plate at which the processing tool contacts the plate.