Purpose: As the demand for natural cosmetics increases, properly managing production and quality control should be prioritized. Chlorogenic acid (CGA), epicatechin gallate (ECG), and rosmarinic acid (RMA) were selected to validate the cosmetic composite LOL, a mixture of 50% EtOH extract of Ligularia stenocephala (LS), Orostachys japonica (OJ), and Lavandula angustifolia (LA). Methods: Highperformance liquid chromatography with a diode array detector (HPLC-DAD) was used to simultaneously analyze the three LOL compounds from LOL (Ligularia stenocephala, Orostachys japonica, Lavandula angustifolia). Linearity, accuracy, and precision analyses were performed using HPLC-DAD, and the anti-oxidative effects were evaluated through a 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assay. Results: All three extracts showed a high DPPH radical-scavenging effect, and the detected marker compounds showed significant linearity (R2 ≥0.9997). The limit of detection (LOD) of CGA, ECG, and RMA was 0.83 µg/mL, 0.33 µg/mL, and 0.20 µg/mL, respectively. Meanwhile, the limit of quantification (LOQ) of CGA, ECG, and RMA was 2.51 µg/mL, 0.99 µg/mL, and 0.61 µg/mL, respectively. Method validation showed acceptable precision (intra-and inter-day precision, CGA, ECG, and RMA, 1.77, 1.42, 0.80% and 1.09, 0.72, 1.42%, respectively) and recovery (CGA, ECG, and RMA, 102.00%–117.78%, 94.40%-108.06%, and 93.79%–107.05%). Conclusion: The contents of the three markers were 13.99 µg/mL CGA, 8.28 µg/mL ECG, and 8.40 µg/mL of RMA, respectively. This study also suggests that the developed method can validate the LOL cosmetic composition quality control process
