Magnetic properties of single crystalline Ga1−xFexSe have been measured. This material is in the new class of diluted magnetic semiconductors based on the III–VI semiconductors. The magnetization versus field for an x=0.05 sample deviates from the linear response seen previously in Ga1−xMnxSe and Ga1−xMnxS and reaches a maximum of 0.12 emu/g (<7% of the expected saturation value) at 1.8 K in 7 T. Ga1−xFexSe exhibits an anisotropy below 2 T from 5 to 400 K with the hard axis perpendicular to the GaSe planes. Neither the broad peak observed from 119–195 K in Ga1−xMnxSe nor the Curie–Weiss behavior observed above 75 K in Ga1−xMnxS are observed in Ga1−xFexSe. The sharp cusp at 10.9 K in Ga1−xMnxS (characteristic of longer range ordering) is also not observed in Ga1−xFexSe in temperatures down to 1.8 K. In 0.1 T in temperatures between 50 and 400 K, the magnetization drops to a roughly constant 0.004 emu/g. Below 5 K, the magnetization approaches a constant value of approximately 0.12 emu/g. The magnetic behavior of Ga1−xFexSe is consistent with Van Vleck paramagnetism.