The PCR-RFLP technique was used to identify the various Tilapia species in the River Nile (EL-Serafyet al. 2003). The DNA genome of Tilapia species and their hybrids are represented in Fig. l. The PCR products of 18s srRNA gene for for Tilapia species and their hybrids are represented in fig. l. the PCR products of 18s srRNA gene for Tilapia species and their hybrids appeared at length ~200 bp fig 2.