The present application discloses a self-powered sensing method and sensing device for spheroidal robot, which belongs to the technical field of robot attitude sensing. The design feature is structure of the spheroidal robot, comprises: a spheroidal object (1) and 26 electrode groups (2); the spheroidal object (1) includes 18 regular octagonal surfaces, 8 regular hexagonal surfaces and 24 quadrilateral surfaces; the electrode group (2) is arranged on each regular octagonal surface and each regular hexagonal surface; the electrode group (2) includes a first outer layer semicircular ring electrode (2-1), a second outer layer semicircular ring electrode (2-2) and an inner ring electrode (2-3). The present invention aims to provide a self-powered sensing method and sensing device for spheroidal robot to sense the posture of the spheroidal robot.