In this work, we present the synthesis, FT-IR and NMR spectroscopic characterization, and X-ray single-crystal structural study of the heterocyclic compound rac-2-thiohydantoin-methionine, C6H10N2OS2, also known as rac-5-(2-methylthio-ethyl)-2-tioxo-imidazolidin-4-one. This material crystallize in the triclinic system, space group P-1 (No 2), Z = 4, with two independent molecules in the asymmetric unit. In the supramolecular structure, the molecules are linked by N-H center dot center dot center dot O and N-H center dot center dot center dot S hydrogen bonds forming infinite bi-dimensional chains along the [100] direction, with graph-set motif R-2(2)(8) and C-2(2)(9).