A power converter, a control circuit and a control method for the same. Ground references of a first controller and a second controller are different to isolate drive signals of a first transistor and a second transistor. Thus the first transistor and the second transistor are controlled to be switched between on and off alternatively to achieve power conversion. The circuit is simple in structure and easy to implement with a low cost. The ground reference of the first controller is an intermediate node of a bridge arm of the power converter, so as to facilitate sampling and acquiring a feedback signal, thereby achieving closed-loop control of the power converter.