Abstract: The use of regression analyses to explain the relationship between various biometric characters of pearl oyster P. margaritifera are found to be most suitable. It can be used to asses this pearl oyster which have been extensively exploited in Red Sea. Pinctada margaritifera is more wide spread among the Pinctada species, occurring across the Indian and Pacific Oceans and in the Eastern Mediterranean Sea. Coastal survey was done during the period from March 2005 to April 2007 covering area more than 600 km of the proper coast of Red Sea, Egypt. Collection of P. margaritifera was done using snorkeling and SCUBA diving in the studied area. The most abundant sites inhabited with the present studied species were divided into two parts, the Northern part which includes areas from Eash El-Malaha to the NIOF marine station near Hurghada city and the Southern area from Shalatein to Wadi El-Hour area. The Northern population of P. margaritifera consisted of larger shell sizes and weights than the Southern area. This was attributed to type of natural food and water quality. The relationship between the shell length and other shell dimensions is generally positive and linear, which indicates isometric growth pattern in the shell of P. margaritifera population of studied area. The length-weight relationship showed a strong positive correlation in a curvilinear pattern with isometric growth form. The results of the condition index indicated that larger values were achieved during summer months and it was expected to be related to the changes in gonad condition more than to the somatic growth of the animal. Seasonal variations in condition index also reflects the importance of seasonal changes in the metabolic activities of the species under study.