The traditional utility function form cannot be used to study the influence of individual attributes on the perceived utility of transit information .In order to overcome this issue ,a modified utility function form is developed to study the impact of dynamic transit information onto the choice behavior of commuting departure time .According to the results of the preliminary model ,independent variables whose t-test are significant are kept and used to develop two modi-fied models ,with one using traditional and the other using modified utility function form respectively .The comparison be-tween the two models shows that the one with the modified utility function form has a better model performance than the one with the traditional utility function form .The study results also indicate that the gender and income attributes ,whose t values are 2 .02 and-2 .25 ,have a significant impact on the perceived utility of riding time .In addition ,the education level has ,which has at value of 2.03,a significant impact on the perceived utility of crowding level .It is also found out that ,when the riding time takes its mean and the crowding level is 0.7 ,their utility ratio is 1.54∶1 .The ratio reveals that the riding time is the most important factor to influence the departure time choice of transit commuters .