A method for measuring ambrisentan content by high performance liquid chromatography, the chromatographic conditions being as follows : an octadecylsilane bonded silica gel is selected as a filler, having a column length of 250 mm, detection wavelength of 220 nm, column temperature of 35°C and flow velocity of 1.0 ml/min; and elution is conducted according to gradient by using reversed-phase high performance liquid chromatography, wherein the mobile phases are a phosphate buffered solution and a polar organic solvent, the phosphate buffered solution is phase A, the polar organic solvent is phase B, and an organic solvent of the phase B in the mobile phases is acetonitrile. By using a reversed-phase high performance liquid chromatography, a test solution and a contrast solution are prepared, 20 μl of the test solution and the contrast solution are measured respectively to be injected into a chromatographic instrument, a chromatogram is recorded, the peak area is calculated according to an external standard method, and folding and drying are conducted so as to complete measurement of the ambrisentan content. The present invention overcomes the deficiency of no ambrisentan content measurement and analysis method existing currently, may meet the requirements for research, development and production, and may effectively conduct relatively strict and effective control on ambrisentan content.