ABSTRACT. – The feeding activity of the sesarmid crab Perisesarma eumolpe helps to maintain the trophic pathways of mangrove forests. This crab is noted as a keystone species of the mangrove ecosystem. The feeding ecology of mangrove sesarmid crabs in the East Coast of Peninsular Malaysia was investigated with laboratory experiments using the leaves of three mangrove species, Avicennia lanata, Bruguiera gymnorrhiza and Ceriops decandra, under different conditions (i.e., fresh and senescent). Perisesarma eumolpe crabs were given access to the fresh or senescent leaves of the three mangrove species for 48 hours. Fresh C. decandra and senescent A. lanata leaves were the most consumed, representing 73.4 % and 73.7 % of the total leaves consumed, respectively. Bruguiera gymnorrhiza was the least consumed in both the fresh (8.5 %) and senescent (43.0 %) forms. Fresh C. decandra leaves had a relatively high moisture content (56.8 %) and low carbon/nitrogen (C/N) ratio of 0.47. Senescent A. lanata had a low moisture content (18.7 %) and C/N ratio (0.56). Sesarmid crabs are subject to desiccation stress and may partly depend on the low-salinity fluid provided by the leaves. Therefore, sesarmid crabs might need to obtain water from more succulent leaves. These results suggest that the feeding preferences in the sesarmid crab P. eumolpe are influenced by either the higher moisture or higher nutritional contents (C/N ratio) of the foods.