This study deals with the park and ride system of transportation for commuters along a railway line. In particular, JR Sanyo line in Hiroshima Urban Area was chosen in order to achieve the object of this study. The each of generalized costs of a railway, private cars and park and ride was calculated and evaluated.
The obtained major results are mentioned as follows: (1) The generalized costs of park and ride are about 80 to 90 percent of private cars'. This range is due to parking fee at a starting station. (2) The generalized cost of park and ride is presented the first equation composed on gas price and parking fee. (3) When the situation of economy is steady, transportation demand of a private car is inclined to increase.