Four flavans, named as (+)(2R,3S) afzelechin (1), (-)(2R,3R) epiafzelechin (2), (-)(2R,3S)afzelechin-(4α-8)(2R,3S) afzelechin (3) and (-)(2R,3S) afzelechin-(4α-8) (2R,3R)epiafzelechin (4), were isolated from ethanolic extract of the leaves of Ficus microcarpa L. for the first time. These compounds were evaluated antiviral effects in vitro towards herpes simplex virus (HSV). Flavans 1 and 2 exhibited low toxicity to rabbit kidney primary cells, moderate antiviral activity against HSV-1 with IC50 values of 0.49 and 0.55 mg mL-1, and therapeutic indexes (TI) of 4.31 and 3.19, respectively. According to cytotoxity and cytopathic effect (CPE) assays, they can be recommended as reference markers for quality control of Folium Fici microcarpae. Other seven known compounds, such as (+)catechin (5), phaseic acid (6), benzoic acid (7), 4-hydroxy-benzoic acid (8), phloroglucinol (9), daucosterol (10), and β-sitosterol (11), were also identified.