The present investigation was carried out at Faculty of Agriculture Saba Basha, Alexandria University and Sabahia Agricultural Research Station during two succesive seasons 2013-2014 and 2014-2015 from nature population of Stevia (Stevia rebaudiana Bertoni) in order to study the genetic improvement through selection for different Stevia genotypes. Ninteen stevia accessions were collected from healthy plants of nature population and selected randomly. The data showed high significant variations between all tested genotypes and there is high genetic diversity between these genotypes and this might be, due to the open pollination for these genotypes for several years and theses genotypes could used in the future in breeding programme. Also, it can conculad that the difference in rebaudioside A due to the difference in the genetic and the negatively correlation between stevioside and rebaudioside-A. can be partially explained by the biosynthetic relationships between the individual glycosides because stevioside is the substrate for the synthesis of rebaudioside A.