The invention relates to a device (50) for centering a movable structure (4) on a stationary structure (5) of a nacelle, comprising: a centering pin (52) mounted on a pin holder (54) attached onto the movable structure (4) or onto the stationary structure (5), the centering pin (52) having a central axis (56) and a receiving bore (60) mounted onto a bore holder (62) attached onto the stationary structure (5) or onto the movable structure (4), said receiving bore (60) being capable of receiving at least the centering pin (52), characterized in that the centering device (50) also comprises a movable interface system, capable of overlapping the central axis (56) of the centering pin (52) and the central axis of said interface system or of the receiving bore (60) and capable of receiving said centering pin (52) in a central opening, and a locking means capable of locking said interface system. The invention also relates to a nacelle including such a device (50).