Pd5InSe has been prepared from the elements. The use of iodine as a mineralizing agent enables the synthesis of single-phase powder samples as well as of single crystals. Pd5InSe is stable in cold air, but reacts to give Pd, In2O3 and Pd4Se at 400 °C. The crystal structure of Pd5InSe was determined from single-crystal X-ray diffraction data (space group P4=mmm, a = 4.0255(7), c = 6.972(1) Å, z(Pd2) = 0.28111(8)) and belongs to the Pd5TlAs-type structure with full occupation of all atomic sites. EDX analysis on the single crystal (Pd5.0(1)In0.99(3)Se1.0(1)) confirms the stoichiometric composition. The relationship to the cubic close packing (Cu-type structure), which may be visualized by the crystal chemical formula Pd4PdTlAs⃞, is proven by a Bärnighausen symmetry tree.