This paper investigated the determinants of the rate of return on investment using78 listed firms in Egyptian Stock Exchange. We used a panel data procedure by applying random effects model using Generalized Method of Moments estimation. The main results showed that the determinants of the return on investment were more effective in service sector than in productive sector. Also, the return on investment in firms with age less than 25 years was more affected by its determinants than firms with age more than 25 years. Add to that, the determinants of the return on investment had more effective role in explaining the changes in the return on investment when operating and financial risks were low. With the absence of role duality, the determinants of the return on investment played a powerful role to clarify the changes in the return on investment. Moreover, the changes in the return on investment well explained by its determinants in firms with large board size. In the light of these results, we provided some recommendations for investors and policy makers of firms.