Nowadays local authorities try to solve problems related to the environmental sustainability of the cities through various urban logistics measures, which directly and indirectly affect the urban food supply system. This paper presents an ongoing research on the urban food transport system and its impact on the city environmental sustainability. The research analyses the city logistics project for food transport implemented in Parma, Italy, in order to identify external costs indicators that help policymakers in evaluating the environmental sustainability of different logistics measures. According to this state of the research, the paper aims at suggesting a methodological framework to estimate the urban food demand, the urban food supply and the urban food transport. These sub-system provide the baseline scenario to evaluate the external costs reduction obtained by the Parma's project.