The widely used analgesic drugs are associated with several harmful effects, which initiate search for new drug development from medicinal plants with better therapeutic efficacy and minimum toxicity. Rhizophora mucronata is a very popular mangrove plant which has been used as ethno-medicine from ancient time. In the present study the ethanolic extract of Rhizophora mucronata L. leaves was found to be safe upto 2gm/kg body weight (orally) in mice in acute toxicity study. The extract in 200 mg/kg body weight dose (orally) showed significant inhibition in acetic acid induced writhing response in mice. In the hot plate method, it increased the latency period than control to some extent, but in tail immersion test, did not showed any significant result. Present study revealed that the ethanolic extract of Rhizophora mucronata L. (Sunderban mangrove) leaves is rich in tannin, flavonoids, polyphenols and possess potential peripheral analgesic and mild central analgesic action.