We herein provide an experimental investigation of the gallides RE2Rh3Ga (RE = Gd, Dy, Ho, Er) regarding their magnetic properties and magnetocaloric effect (MCE). All of these RE2Rh3Ga intermetallic compounds crystallized with the Mg2Ni3Si type structure, space group R–3 m and are ordered magnetically at low temperatures. Large reversible MCEs around their own ordering temperature were observed in all RE2Rh3Ga compounds and their magnetocaloric parameters including the maximum magnetic entropy change, refrigerant capacity, and temperature-averaged entropy change are comparable to those of some recently reported candidate materials with prominent performances, making them considerable for cryogenic MR applications.