The application of auto-hydrolysis of Tiquilia paronychioides (Phil.) A.T. Richardson aimed to determine the increase in quercetin concentration. Auto-hydrolysis was developed with aerial parts of T. paronychioides in aqueousmedium at 25°C with 20 rpm by 0, 2, 5, 8, 24, 48, 96 and 168 h, with 3 repetitions per test. Quercetin standards at concentrations of 5 to 80 ppm and auto-hydrolyzed extracts were evaluated by HPLC. The auto-hydrolyzed extracts showed Quercetin peaks from 8 h. Quercetin concentrations at 48, 96 and 168 h were 0.036 ± 0.0048, 0.033 ± 0.0105 and 0.026 ± 0.0068 mg quercetin/g, respectively, being statistically equal. In conclusion, the auto-hydrolysis of T. paronychioides generates the highest concentration of quercetin at 48 h.