Abstract: Objective:The paper explored the rationality of the determination of tea polyphenols in tea seed oil by the method of Folin phenol method and the determination of total catechin contents in tea seed oil by high performance liquid chromatography (HPLC). Methods:The contents of tea polyphenol and catechins in tea seeds, tea seed oil and oil cakes were compared and determined by Folin phenol method and high performance liquid chromatography (HPLC), analyzed the interference of phenolic hydroxyl-containing fat-soluble substances such as vitamin E in tea seed oil on the determination of tea polyphenol contents in tea seed oil by the Folin phenol method. Results:The catechin content was calculated by 60%~80% of the contents of tea polyphenols determined by Folin phenol method, which was much higher than that determined by HPLC. Numerous repeated experiments using Folin phenol method and HPLC to test the contents of polyphenols and catechin in tea seed oil respectively indicated that RSD was 7.21% and 1.99%. The content of tea polyphenols in the tea polyphenol colloid was determined by Folin phenol method, results showed that the RSD of these groups were 0.70%, 1.13% and 0.63%. Then the tea polyphenol colloid was used again to do the recovery rate experiment and the value was 90.87%~109.00%. Conclusion:The method for extracting and determining tea polyphenols in tea seed oil is reliable. Forin phenol method was not suitable for determining the contents of tea polyphenols in oils and fats, the distribution of tea polyphenols in crude tea seed oil was uneven.