Use of railway traortation system for traorting of goods and passengers is highly expanding in the world. On the other hand, most of the existing trains are powered by diesel locomotives with relatively high fuel consumption. Since the power transmission system of these locomotives is similar to electric hybrid vehicles, by adding an electric power supply, these locomotives can be converted to hybrid-electric locomotives. The use of an appropriate control strategy can significantly reduce fuel consumption of locomotives. Improving travel quality is one of the important factors which is considered in the design of vehicle controllers. One of the purposes of travel quality is following an optimal speed profile with the least error. In other words, the distance between the start point and the destination should be traveled with minimum speed drop as well as the extreme and consecutive braking, preventing the occupant’s dissatisfaction. Reducing the braking noise, especially in railway traortation, is another aspect of travel quality. Also, to ensure train safety while driving, it is necessary to control the train speed in such a way to avoid slipping of the train wheels on the slippery railways in different weather conditions. A very suitable tool for achieving these goals is fuzzy look-ahead controller that is designed in this project. The fuzzy look ahead controller, controls the speed of the train in order to reduce fuel consumption, increase the quality of travel and minimizes travel time. This is done with regard to the slope of the path, the slope change of the forward path, wet or dry condition of rails, and the speed limits of the path ahead. In this thesis, the GM SD40-2 locomotive, which has been converted into a hybrid electric locomotive by adding a lithium ion battery pack, has been used for simulation. The advantage of the dynamical model used in this study in comparison to the previous models is considering the weather conditions of the path, in particular the condition of wet or dry rails and the temperature of the air. Exerting the effect of wet or dryness of the path in the locomotive model and simulating of the GM SD40-2 locomotive movement in a local path using a fuzzy look ahead controller, increases travel quality along with a relative reduction in fuel consumption and travel time. Keywords: Hybrid locomotive, Fuzzy look-ahead controller, Wheel/rail adhesion, Wet rail, Water temperature, Travel quality, Fuel consumption optimization.