Disclosed is a device for adjusting the height of a suspended lamp, which includes at least a guide roller combination, an operating cord, a limiting member, a controlling member and an adjusting shell, the adjusting shell being connected to the lamp, and the guide roller combination and the limiting member being arranged in the adjusting shell, a circumferential end surface of the guide roller combination includes an inwardly recessive roller groove in a radial direction thereof, the operating cord is arranged within the roller groove, one end of the operating cord exits through the adjusting shell and is fixed at an upper end in a lamp moving area range, the other end of the operating cord exits through the adjusting shell to become a free end.
