A triple wavelength spectrophotometry to measure malice acid in green apples was established in this study. The reaction between malic acid and tris-hydrochloric acid buffer solution of malachite green showed that a green ionic association complex with three positive absorption peak locating in 568 nm, 644 nm and 424 nm, respectively, could be found in visible light generated area. Moreover, the malic acid with triple wavelength spectrophotometry and its related reaction condition and absorption spectral character were investigated. The result showed that the molar absorption coefficient of performance was 5.88×104 L/(mol·cm), and the quality concentration of malic acid was found to be 0.008~1.900 mg/L, conforming to Lambert-Beer's Law. It was also found that the limit of quantitation was 0.003 2 g/100 g, and the adding standard recovery rate was 98.23% to 102.9%, with a relative standard deviation at 1.8%~2.4%. This method could be used for the determination of malic acid in green apple.