Abstract: Presence of strong secondary currents and their interaction with the topography of the channel bed in river bends have significant effects on the distribution of longitudinal and transverse velocity and consequently the shear stress across the width and length of a bend. Flow in river bends has been investigated by several researchers, resulted in introducing a variety of different equations for identifying the parameters of flow in river bends. However, the proposed equations do not provide a good solution especially in sharp bends. In this research, we carried out a set of laboratory tests to investigate the distribution of the longitudinal velocity in sharp river bends. The tests were performed in the laboratory of hydraulics department of EPFL University in Switzerland, with discharges of 63, 89 and 104 L sec-1 on a developed topography. Based on the test results, we presented an experimental equation includes two, a power and a sinuous, segments to estimate the longitudinal velocity in sharp river bends. Having determined the longitudinal velocity profile using the new model and also some available models, we calculated the Standard Error of the predicted against the observed results from laboratory experiments. We found that the Standard Error of the new model is considerably lower than the Standard Error of the other models, confirming the high accuracy of the new equation on predicting the longitudinal velocity profile in sharp bends.