A centralized voltage control apparatus is connected via a communication network to a plurality of local voltage control devices each controlling a corresponding voltage controller connected to a distribution line of a distribution system. The centralized voltage control apparatus includes: a voltage distribution determination unit that calculates a control variable for each of the voltage controllers on the basis of a measured value of voltage at each measurement point of the distribution line and a proper voltage range at each measurement point; and a tap position determination unit that gives a command value to each of the local voltage control devices on the basis of the control variable. At least a part of the proper voltage range at each measurement point is determined on the basis of an estimated value of a change in voltage in a section in which voltage is not measured on the distribution line.