In the last four decades, many equations have been proposed to estimate the shear strength of Steel Fiber Reinforced Concrete (SFRC) beams. However, in terms of accuracy and uniformity of the prediction, there is considerable diversity between existing test results and researchers' predictions. In this study, by using the basic principle of mechanics and considering the slenderness effect of SFRC beams without stirrups, a new design expression is proposed for the shear strength of SFRC beams. The proposed equation and researchers' predictions are compared to the test results of 170 SFRC beams without stirrups. It is found that the proposed equation shows good agreement with regard to the existing test results.