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The microstructure and magnetoresistance properties of the polycrystalline La_0.67Ca_0.3Mn_1−xV_xO₃ were systematically investigated as a function of V-doping level. X-ray powder diffraction indicated that the substitution of Mn by V produced no structural change and only the diffraction lines for cubic perovskite were obtained for all samples. The detailed EDX analysis showed the existence of two phases in La_0.67Ca_0.3Mn_1−xV_xO₃ (x=0.03, 0.06, 0.1, 0.15 and 0.25) samples. The temperature dependence of resistance showed two maxima in the V-doped sample for x≤0.15, and the peak value of magnetoresistance (MR) around insulator–metal transition temperature was increased with V-doping. Double maxima in the resistance–temperature curves were explained by the existence of two phases in La_0.67Ca_0.3Mn_1−xV_xO₃ samples.