Otokuni-gun used to include the entire region which includes present-day Nagaokakyo City and Muko City as well as the present-day Nishikyo and Minami Wards, Kyoto City and a portion of the present-day Fushimi Ward.
現在の長岡京市と向日市の全域、京都市西京区および南区(京都市)、伏見区の一部もかつては乙訓郡に属していた。