In order to determine the effect of regrowth age on the components of yield, chemical composition and polyphenolic profile of Tithonia diversifolia, an experiment was carried out using a randomized block design with four replications in brown soil with carbonate. The treatments consisted of three regrowth ages (60, 120 and 180 days). To establish the functional relationship between the different evaluated indicators and age, linear, quadratic, cubic and Gompertz equations were analyzed, selecting the best fit according to high value of R2, high significance of the terms and of the equation, low standard error of estimation and of terms, and significant contribution of terms and of the equation. The equations of the best fit for the functional relationship between the different evaluated indicators and age, in each seasonal period, were quadratic. There was an increase in yield of dry matter, NDF, ADF, ADL with age, with maximum values at 180 days (23.92 t/ha, 47.63, 31.38 and 21.01%, respectively); edible biomass, CP, cellular content, in