A mobile apparatus, a chassis for the mobile apparatus and an angle change method for the chassis are provided. The chassis includes: a chassis body including a first body and a second body, with each of the first body and the second body including a bottom surface and a support surface arranged opposite to each other; an angle change device, which is respectively connected with the first body and the second body, disposed between the first body and the second body in an arrangement direction of the first body and the second body, and configured to change an angle between the bottom surfaces of the first body and the second body; and a moving device, configured to move the chassis body.