Abstract: C-,Ag-banding chromosomes and synaptonmal complex (SC) of Tilapia nilotica have been reported.The conventional karyotype of Tilapia nilotica consists of 22 pairs of chromosomes and can be classified into three groups;4 pairs are submetacentric (Nos.6,8,15,21);17 pairs subtelocentric (Nos.2,3,4,5,7,9,10,11,12,13,14,16,18,19,20,22) and a pair telocentric (No.1).The C-bands located mainly at the centromeric regions and Nos.6,8,15 chromosomes have been darkly stained on the short arm Two to six NORs are distributed on the short arm of submetacentric (Nos.6,8,15).Twenty-two SC are formed during the pacytene stage and no heteromorphic chromosomes have been found.The SC karyotype of Tilapia nilotica also has been constructed.