Objective: To explore the prospective effect of dietary intake of total fat and fatty acids on menarcheal timing among girls,and to provide a theoretical basis for preventing the early puberty development of Chinese children. Methods: Using the data from 1997-2015 China Health and Nutrition Survey (CHNS), 1 240 girls aged 6-13 with menarche information, baseline dietary survey data and at least one follow up assessment were selected. Cox regression analysis was performed to examine the prospective effect of dietary intake of total fat and fatty acids before menarche on age at menarche. Results: The mean baseline age of the participants was (8.3±1.8). After adjustment for year of birth, residence, household income, dietary energy intake and body mass index Z score at baseline, girls in the highest quartile of intake of total fat and polyunsaturated fatty acid (PUFA) had a 30% and 34% higher probability of experiencing menarche at an earlier age than those in the lowest quartile [ HR(HR 95%CI )=1.30 (1.01~1.68)，1.34(1.05~1.70)]. After adjusting for the confounders, there were no correlations between the intake of saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) and the onset of menarche [ HR(HR 95%CI )=1.24(0.98~1.58),1.25(0.97~ 1.62 )]( P >0.05). Conclusion Higher dietary intake of total fat and PUFA before menarche may lead to earlier age at menarche and no correlation between intake of SFA and MUFA before menarche with age at menarche is found among Chinese girls.