Tea polyphenols and phytic acid both can be used as food preservative. In this paper， the mixed solutions concentrations of tea polyphenols and phytic acid were simultaneously determined by spectrophotometr， and the interference was eliminated. The results showed that phytic acid had no effect on the coloration of tea polyphenols， and the concentration of tea polyphenols in the mixed solution could be determined immediately by ferrous tartrate coloration method. Tea polyphenols and phytic acid both had color development when the polyferric chloride-sulfosalicylic acid was a chromogenic agent， and the color development ability of phytic acid were affected by the mass concentration of tea polyphenols in the mixed solution. The interference of tea polyphenols on the color development ability of phytic acid could be eliminated by the mathematical simulation method， and the standard curve of phytic acid were obtained. By this method， the optimal determination range was the tea polyphenol mass concentration of 0-0.300 mg/mL， the phytic acid mass concentration of 0-3.000 mg/mL， and the recovery rate of 96%-103%. The method is simple to operate and has high accuracy， and it can provide a theoretical basis for simultaneous determination of mixed components.