The present disclosure discloses a multipath current source switching device, including a switching control unit, N current paths, and N loads. Each current path is formed by a constant current source circuit and a switching circuit. One terminal of a first load is coupled to a load power supply, and the other terminal of the first load is coupled to an output terminal of a constant current source circuit of a first current path and one terminal of a second load; one terminal of an ith load is coupled to the other terminal of an (i−1)th load and an output terminal of a constant current source circuit of an ith current path; and the switching control unit controls an output current of a corresponding constant current source circuit through a corresponding switching circuit. When the circuits are switched, an output voltage of a switching circuit of a current path to be switched off is decreased to zero according to a preset voltage variation quantity, and an output voltage of a switching circuit of a current path to be switched on is increased to a highest operating voltage according to the preset voltage variation quantity, such that a current on a load does not exceed a preset current and is not zero during switching. N is an integer not less than 2, and i is equal to 2, 3, 4, . . . , N.