The present invention provides a dual-power source automatic change-over switch. The dual-power source automatic change-over switch comprises a shell, a control box and a switch group; the switch group comprises a plurality of static contact assemblies and a plurality of moving contacts corresponding to the static contact assemblies; each static contact assembly includes a load binding post, a I-path binding post and an II-path binding post; each moving contact is arranged among the load binding post, the I-path binding post and the II-path binding post of a corresponding static contact assembly rotationally through a rotation shaft; each moving contact is at least provided with two moving contacting points which are in electric connection; and the moving contact rotates forwards and reversely under the control of the control box, so that two moving contacting points of the moving contacting points on the moving contact can conductively contact with the load binding post, the I-path binding post and the II-path binding post selectively, or conductively contact with the load binding post and the II-path binding post correspondingly. Since structural design is optimized, the safety performance of electric equipment is improved, and the stability of the automatic change-over function of the dual-power source automatic change-over switch is guaranteed.