The invention discloses a storage battery pack control method and system, which comprises the steps which are as follows: voltages of each storage battery are collected; the voltages of each storage battery are mutually compared to obtain a maximum voltage, a minimum voltage, and a voltage difference between the maximum voltage and the minimum voltage; then the charging-discharging state of the storage battery pack is judged; when the storage battery pack is under the charging state, the sizes of the voltage difference and a first preset value are judged; and when the voltage difference is equal to or more than the first preset value, a discharging command is generated to discharge the storage battery matched with the maximum voltage; when the storage battery pack is under the dischargingstate, the sizes of the voltage difference and a second preset value are judged; and when the voltage difference is equal to the second preset value, a command for reducing the system power is generated and is transmitted to a vehicle control system. The method can detect the voltages of each storage battery; moreover, when the consistency between single storage battery is destroyed, the problem of damaging the storage battery pack caused by overlarge difference between single storage batteries can be avoided through the means such as discharging or reducing the power, etc.