The ethanol extract of leaves of the mangrove Aegiceras corniculatum Blanco (Myrsinaceae) wasscreened for its antinociceptive, antidiarrhoeal and cytotoxic activities. The extract producedsignificant writhing inhibition in acetic acid-induced writhing in mice at the oral dose of 250 and500 mg/kg body weight (P < 0.001), which was comparable to the standard drug diclofenacsodium at the dose of 25 mg/kg of body weight. When tested for its antidiarrhoeal effects oncastor oil induced diarrhoea in mice, it increased mean latent period and decreased the frequencyof defecation significantly at the oral dose of 500 mg/kg body weight (P<0.05; P<0.01) comparable to thestandard drug loperamide at the dose of 50 mg/kg of body weight. Moreover, when tested fortoxicity using brine shrimp, the extract showed potent activity against the brine shrimp Artemiasalina (LC50 10 mg/ml). The overall results tend to suggest the antinociceptive, antidiarrhoeal andcytotoxic activities of the extract.