In order to study bio-molecules damage protective effect and free radical scavenging capacity of Coriandrum sativum L. (coriander), Folin-phenol assay was used for estimating total polyphenol of coriander. Gel electrophoresis was performed for detecting DNA and protein damage protective effect of coriander. Free radical scavenging capacity of coriander extract was evaluated using DPPH assay. ORAC assay was used to confirm the value of oxygen radical absorbance capacity. The result showed that the content of total polyphenol was 4.054μg/mg and the minimum protective concentrations on DNA and bull serum albumin were 4.0μg/mL and 125.00μg/mL. The IC₅₀ value for DPPH radical scavenging ability was 0.17μg/μL while the ORAC value for antioxidant capacity was 485.3. The result indicated that the coriander extract had distinct antioxidant activity.