Since 2001, an increasing income inequality can be observed in most EU Member States. On aggregate level, this development is not reflected by statistics. They indicate growing average wages in real terms. Detailed statistics on average wages of different income classes reveal a tendency of diverging income distribution. Employees with low incomes even have to cope with decreasing wages in real terms. At the same time, energy prices have risen significantly due to exceeding peak oil and reinforcing oil scarcity. Considering these trends the question arises on how the income distribution in combination with increasing transport costs influences the mobility behaviour of persons in different income groups. The thesis addresses this question by performing a system-based analysis of income distribution impacts on mobility behaviour. The integrated macroeconomic, transport and environmental model ASTRA is chosen as basic modelling framework for this work. The model has been developed since 1998 for the purpose of assessing transport strategies and is based on System Dynamics methodology. It consists of nine modules interacting with each other and covers all current 27 EU Member States plus Norway and Switzerland. The major benefit of applying the ASTRA model is determined by its integrative approach, considering feedback structures between economic, transport and environment systems. Considering different explanatory approaches on income distribution a model is developed simulating the dynamics of personal income distribution in 18 European countries. Based on the requirements of the transport and vehicle fleet module, the population is allocated into five characteristic income groups. Finally, the model is validated for the period from 1990 to 2004 with micro-census data extracted from the Luxemburg Income Study database.