Embodiments of the present disclosure provide a detection device. The detection device includes: a fixed member fixedly mounted to a target position; a first movable member arranged to face towards and in parallel with the fixed member, and movably connected to the fixed member by a first elastic member; at least one first electrode, having one end being fixed to the fixed member and the other end extending towards the first movable member along a first direction; and at least one second electrode, having one end being fixed to the first movable member and the other end extending towards the fixed member in a second direction, the second direction being parallel to the first direction. Embodiments of the present disclosure also provide a fatigue detection system.