An evaporated fuel purge control apparatus includes a purge control valve arranged in a purge passage between a canister and an intake passage of an engine, the purge control valve being switched on and off in accordance with a control factor, the control factor indicating a duty ratio of an on-time of the purge control valve within a duty cycle to a total duty-cycle time, a detecting part for detecting an operating condition under which the engine is operating, and a flow rate control part for setting a control factor for the purge control valve in accordance with the operating condition detected by the detecting part, the control factor set by the flow rate control part allowing a flow rate of evaporated fuel fed from the canister into the intake passage through the purge control valve to be maintained at a constant level when the operating condition of the engine changes.