The invention discloses a voltage out-of-limit adjusting method in the technical field of power supply system control. The voltage out-of-limit adjusting method comprises the following steps of: obtaining power flow interface data and determining nodes which take part in voltage adjustment; calculating power flow distribution of a power supply system according to the power flow interface data, so as to obtain voltage of each node; correcting and checking each node which takes part in the voltage adjustment, determining a voltage out-of-limit node and the voltage out-of-limit node with a maximum voltage out-of-limit value, and recording the node with the maximum voltage out-of-limit value as a node N*; carrying out sensitivity analysis on the node N*, calculating a reactive voltage sensitivity matrix of all the nodes which take part in the voltage adjustment to the node N*, and determining adjustment equipment taking part in the voltage adjustment; establishing a comprehensive sensitivity equation and calculating an adjustment amount of each adjustment equipment taking part in the voltage adjustment; adjusting each adjustment equipment taking part in the voltage adjustment according to the adjustment amount; calculating the adjusted voltage of each node; and if no voltage out-of-limit node exists, stopping adjusting. According to the voltage out-of-limit adjusting method disclosed by the invention, the adjustment capacity of the adjustable equipment can be rapidly and accurately calculated, and the security and the reliability of the power supply system are improved.