A 3D sensing device includes a base, an infrared emitting module, a first infrared receiver, a second infrared receiver, a color camera module, a first moving member, a second moving member, a first driving member, and a second driving member. The first moving member and the second moving member are slidably mounted on the base. The first driving member and the second riving member respectively drive the first moving member and the second moving member to slide along the base. The infrared emitting module is mounted on the first moving member. The color camera module is located between the first infrared receiver and the infrared emitter. The second infrared receiver is mounted on the second moving member. The first moving member and the second moving member respectively move the infrared emitting module and the second infrared receiver along the base relative to the first infrared receiver.