The invention discloses a radiator, a heat dissipating assembly, a heat dissipating chassis and a laser and relates to the technical field of laser heat dissipation. The radiator comprises a plurality of heat dissipating parts which are spaced in parallel and extend along a first preset direction; a heat dissipating channel is formed between the adjacent heat dissipating parts; each heat dissipating part is provided with a front and a back which are opposite in a second preset direction vertical to the first preset direction; and a heat dissipating groove which extends along the first preset direction is arranged on the front of each heat dissipating part. The radiator has small processing difficulty, low cost and long service life and is capable of effectively dissipating the heat.