Abstract Magnetic and structural behaviour of materials of composition RInCu 2 (R = rare earth) were investigated. All the compounds ( R = La- Lu) were found to be isotypic and to crystallize with the Heusler L2 1 type structure. The magnetic behaviour of the compounds was studied in the temperature range 2–300 K. The RInCu 2 (R = Sm, Gd, Tb, Dy) compounds are antiferromagnetically ordered at low temperatures T N = 12 K for GdInCu 2, Ce in CeInCu 2 is in a pure trivalent state. LaInCu 2 is Pauli paramagnetic and LuInCu 2 is diamagnetic. No superconductivity was observed for temperatures as low as 1.8 K. The observed magnetic properties result from indirect exchange interaction and crystal field effects and compared to the isomorphous MnInCu 2.