sed to calculate the above parameters. For calculation purposes the following packages have been used: FAO⢠lCLARM Stock Assessment Tools (FiSAT), BASlCA and EXCEL. The values of 'a' and 'b' in the formula W=aLb were found to be 0.0165 and 3.0007 respectively. This was in accordance with data reported from Saya de Mal ha (a= 0.012 and b = 3.160 by Bertrand et al in 1986. The Fulton's condition factor (cf) was also calculated and no general trend was found during the sixteen months of study. The asymptotic length (Loo) was found to be 63 cm and the growth constant K was found to be 0.12 in 1999. The total mortality Z, natural mortality M and fishing mortality F were calculated as 0.65, 0.34 and 0.31 respectively. The Ganado Somatic Index (GS!) was directly related to the Hepato Somatic Index (HIS) between July 1998 and August 1999 and was inversely related for the last two months implying that spawning may have started by September I 999. The length at first capture (Lc50) was found to be 31.8 cm, that is, it exceeded the value of the length at maturity (Lm50) which was found to be below 30 cm. Data were in accordance with those from Saya de Malha and Nazareth bank. However, due to the limited data available and Lethrinus mahsena being a slow growing fish, further studies need to be carried out. A wider sampling time span is thus suggested. The sample was taken from a commercial catch and thus the sample was biased due to gear selectivity. For proper management measures, otolimetry should be performed so as to obtain better age data for analysis. This project having been interrupted in the middle of the sampling period, such data was not available.