CuIn_2n+1 S_3n+2 crystals were synthesized by horizontal Bridgman method using high purity copper, indium, sulfur elements. The phases and crystallographic structure of the CuIn_2n+1S_3n+2 crystals were analyzed by X-ray diffraction (XRD) and the composition of the material powders was determined using the energy dispersive X-ray analysis (EDX). Measurement data revealed that CuIn_2n+1S_3n+2 materials have not the same structure. In fact, CuInS₂ and CuIn₃S₅ crystallize in the chalcopyrite structure whereas CuIn₅S₈, CuIn₇S₁₁ and CuIn₁₁S₁₇ crystallize in the cubic spinel structure.