Novel crystalline Mo-V-M-O (M = Al, Ga, Fe) mixed oxides were prepared by hydrothermal synthesis with Anderson-type heteropolymolybdate and vanadyl sulfate at 175 degreesC in the presence Of (C2H5)(3)NHCl. The obtained Mo6V2Al1Ox mixed oxide was rod-shaped crystal and the X-ray diffraction (Cu K alpha) peaks at 2 theta = 4.7 and 8.2 degrees were observed, which suggest a formation of a super structure in the cross-section of the rod-shaped crystal. The synthesized Mo-V-M-O (M = Al, Ga, Fe) mixed oxides were assumed the same structure of hexagonal unit cell of the space group P6. The mixed oxides after calcination in N-2 flow at 500 degreesC were used for ethane selective oxidation. The catalysts prepared in the presence of (C2H5)(3)NHCl showed higher ethane conversion and selectivity to acetic acid than those prepared in the absence of (C2H5)(3)NHCl.