This paper presents a sensitivity analysis of induced voltages on overhead distribution lines due to some lightning and line configuration parameters variations. The sensitivity analysis was made initially varying just one parameter individually and then was varied whole parameters at the same time analyzed by means of nonlinear regression models. This analysis shows the parameters that have more influence on the induced voltages. It was also obtained an approximate equation to calculate the maximum induced voltage along the line. The obtained equation was also compared with other approximate equations such as Rusck and Jankov.