The invention relates to the technical field of ship power systems, in particular to a pure battery power ship comprehensive power system radial power grid structure and a control method. The power grid structure comprises a direct-current busbar, an alternating-current busbar, a battery pack, a DC/DC converter, a DC/AC inverter and a boosting frequency converter/rectifying and charging integrated device, an isolating switch is connected between the input end of the DC/DC converter and the battery pack, a first direct-current switch assembly is connected between the input end of the DC/DC converter and the direct-current busbar, a second direct-current switch assembly is connected between the output end of the DC/DC converter and the direct-current busbar, at least one section of direct current busbar is connected to the first alternating current busbar through a fourth direct current switch assembly, a DC/AC inverter and a first alternating current circuit breaker which are connected in sequence, and each section of direct current busbar is connected to one section of second alternating current busbar through a third direct current switch assembly, a propulsion frequency converter/rectification charging integrated device and a first alternating current contactor which are connected in sequence; and each section of the second alternating current busbar is connected to a propulsion motor through a second alternating current contactor.