Abstract: We combined physiological theory with classic GIS path planning method,and a model for calculating walking energy expenditure per unit distance was established based on recent physiological studies,and an approach was made to convert road real length on different gradient to corresponding level distance using the model.With this approach,real path lengths were transformed into equal level lengths before being measured.The results show that both gradient and distance are taken into account in this algorithm,and the route provided was more reliable and useful than that by shortest path algorithm for pedestrians.