A system for sharing a battery between mobile terminals, characterized in that the system comprises a mobile terminal of a power supply end and a mobile terminal of a power utilization end, wherein, the mobile terminal of the power supply end comprises a battery of the power supply end, a circuit interface of the power supply end and a power supply control unit of the power supply end, wherein the power supply control unit of the power supply end is coupled with the battery of the power supply end and the circuit interface of the power supply end respectively; the mobile terminal of the power utilization end comprises a battery of the power utilization end, a circuit interface of the power utilization end, a power supply control unit of the power utilization end and a power management unit, wherein the power management unit is coupled with the battery of the power utilization end and comprises a power supply switch subunit; wherein the circuit interface of the power utilization end is coupled with the circuit interface of the power supply end; the power supply control unit of the power supply end is configured to control the battery of the power supply end to supply power to the mobile terminal of the power utilization end through the circuit interface of the power supply end; the power supply switch subunit, coupled with the circuit interface of the power utilization end, the battery of the power utilization end and the power supply control unit of the power utilization end respectively, is configured to control the circuit interface of the power utilization end or the battery of the power utilization end to couple with the power supply control unit of the power utilization end; and the power supply control unit of the power utilization end is configured to supply power to the mobile terminal of the power utilization end; wherein the mobile terminal of the power supply end further comprises: a charging control unit of the power supply end, coupled with the battery of the power supply end, configured to perform charging control to the battery of the power supply end; and a power supply interface control unit, coupled between the circuit interface of the power supply end and the power supply control unit of the power supply end in series and coupled with the charging control unit of the power supply end, configured to control the circuit interface of the power supply end to couple with the charging control unit of the power supply end or the power supply control unit of the power supply end; wherein the power management unit further comprises: a charging and power supply mode control subunit and an electricity quantity detection switch subunit sequentially coupled between the circuit interface of the power utilization end and the power supply switch subunit in series; the mobile terminal of the power utilization end further comprises a charging control unit of the power utilization end coupled with the battery of the power utilization end; the charging and power supply mode control subunit, coupled with the charging control unit of the power utilization end, is configured to control whether the mobile terminal of the power supply end charges the battery of the power utilization end when the mobile terminal of the power supply end supplies power to the mobile terminal of the power utilization end.