Abstract: The preparation of ortho-nitro substituted isomer of flutamide,2-methyl-N-(2-nitro-5-trifluoromehyl phenyl )-propionamide, its melting point,UV,IR,MS,^lHNMR,and¹³CNMR spectral data were replrted .The obvious difference of TLC behavior between this compoundand flutamide offered a method for detecting this compound in impure flutamide。