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X-ray powder diffraction measurements, at room temperature, and magnetic susceptibility c measurements, in the temperature range from 2 to 300 K, were made on polycrystalline samples of Cu 2 FeGeSe 4 and Cu 2 FeGeTe 4 magnetic semiconductor compounds. Magnetization measurements at 2, 4.2 and 77 K in magnetic fields up to 35 T were carried out on Cu 2 FeGeSe 4 compounds. From the analysis of the X-ray diffraction lines, it was found that Cu 2 FeGeSe 4 and Cu 2 FeGeTe 4 have, respectively, stannite and monoclinic structures. The resulting 1ac versus T curves showed that Cu 2 FeGeSe 4 is antiferromagnetic with a Ne  el temperature T N 20 K while Cu 2 FeGeTe 4 is ferrimagnetic with T N 160X1 K. The magnetization and susceptibility results obtained on Cu 2 FeGeSe 4 showed the presence of bound magnetic polarons (BMPs) in agreement with earlier studies made on this type of materials [1,2].