Owing to the biological and ecological importance of the otolith and the significant role of Tilapia nilotica in aquaculture production, in addition to the less information about the relationships between the size in both otolith and fish individuals, this study was carried out. Forty-five fish specimens of variable length and weight Tilapia nilotica (Oreochromis niloticus) were collected from Al-Abbasa fish farms, Sharkia Governorate, Egypt. The lengths and weights of fish and their otoliths were recorded and the mean as well as the standard deviation were estimated. The different relationships between fish and otolith with regard to length and weight were identified by Pearson correlation coefficients. The means of Tilapia nilotica body weight and otolith weight were 225105.7 mg±182402.31 and 55.9743 mg±32.93714, respectively. Moreover, the means of fish body length and otolith length were 172.429 mm±74.8580 and 8.1571 mm±3.54984, respectively. In conclusion, there was a positive linear relationship between the developmental rate of fish and otoliths, taking the weights of fish and otoliths in consideration all over this research