BACKGROUND Pycnocycla spinosa (P. spinosa) a member of the Umbelliferae family is traditionally used for treatment of different ailments. OBJECTIVE This study aimed to evaluate the total phenolic and flavonoid content of P. spinosa extracts (methanol, ethanol and aqueous) and their antioxidant and antimicrobial effects. METHODS The antimicrobial activity of different extracts of P. spinosa was evaluated using micro broth dilution. Total phenolic and flavonoid contents were measured. Their antioxidant effect was evaluated using DPPH assay and β-carotene linoleic acid test. RESULTS P. spinosa ethanol extract with higher-level phenolic and flavonoid contents showed the highest antioxidant and antimicrobial effects, in comparison with the other extracts. Bacillus sp. and Streptococcus sp. showed higher sensitivity to P. spinosa ethanol extract. CONCLUSIONS P. spinosa ethanol extract can be used as a mouthwash for treatment of the oral infections. More clinical and toxicological studies are required for providing its efficacy.