A selective breeding study for live weight based on a fully pedigreed population of GIFT (Genetically Improved Farmed Tilapia) strain was carried out at the Aquaculture Extension Centre, Department of Fisheries, Jitra, Kedah. Progeny were generated in three spawning seasons, 2002, 2003 and 2004. Two lines were created from the 2002 progeny, based on high breeding values (selection line) and for average breeding values (control line). The selection and control lines were then used as parents to produce progeny in the 2003 spawning season, and the progeny of the 2004 spawning season were produced by using the selection and control lines of 2003. The present study indicated that genetic enhancement of growth rate had been achieved through selective breeding. The estimated genetic gains from the three generations of selection ranged from 6 to 13 percent and it is in good agreement with similar studies reported by other researchers.