The present study examined the determinants of public trust in railroad companies. The constructs studied were as follows: trust in companies, familiarity toward companies, recognition of company values, perceived frequency of traffic accidents, perceived involuntary risk, perceived function as watchdogs of other institutions, and perception of safety measures. We conducted a survey in the Tokyo Metropolitan area and obtained answers from 1,081 respondents. The postulated model was tested using structural equation modeling procedures. The results indicated that the proposed model fits the data very well. It was shown that perceived function as watchdogs, perception of safety measures, recognition of company values, and familiarity had direct effects on trust.