A charge control device for a battery mounted on a vehicle, the vehicle comprising an engine, a generator driven with power of the engine, the battery configured to be chargeable with electric power generated by the generator, and auxiliary machinery operated with electric power of the battery, the charge control device comprising: a battery current sensor that detects the charge-discharge current of the battery; an SOC detector that is configured to detect a state of charge, SOC, of the battery; a load current detector that is configured to detect a load current of the auxiliary machinery; and a charge controller that is configured to control charging into the battery to be in a target SOC, based on a detected value of the load current of the auxiliary machinery and a detected SOC, wherein in response to detection of a transition in which a magnitude of the discharge current from the battery transitions from a value smaller than a predetermined threshold value to a value larger than the predetermined threshold value: the charge controller controls a generated voltage by the generator, based on a magnitude of the detected value of the load current of the auxiliary machinery prior to the transition, during a time period until a specified time has elapsed after the detection of the transition, and the charge controller controls the generated voltage by the generator, based on a magnitude of the detected value of the load current of the auxiliary machinery detected by the load current detector, during a time period after elapse of the specified time. a battery current sensor that detects the charge-discharge current of the battery; an SOC detector that is configured to detect a state of charge, SOC, of the battery; a load current detector that is configured to detect a load current of the auxiliary machinery; and a charge controller that is configured to control charging into the battery to be in a target SOC, based on a detected value of the load current of the auxiliary machinery and a detected SOC, wherein in response to detection of a transition in which a magnitude of the discharge current from the battery transitions from a value smaller than a predetermined threshold value to a value larger than the predetermined threshold value: the charge controller controls a generated voltage by the generator, based on a magnitude of the detected value of the load current of the auxiliary machinery prior to the transition, during a time period until a specified time has elapsed after the detection of the transition, and the charge controller controls the generated voltage by the generator, based on a magnitude of the detected value of the load current of the auxiliary machinery detected by the load current detector, during a time period after elapse of the specified time. the charge controller controls a generated voltage by the generator, based on a magnitude of the detected value of the load current of the auxiliary machinery prior to the transition, during a time period until a specified time has elapsed after the detection of the transition, and the charge controller controls the generated voltage by the generator, based on a magnitude of the detected value of the load current of the auxiliary machinery detected by the load current detector, during a time period after elapse of the specified time.