Income inequality is a very useful concept in determining the influence, on a population, of two constituents that play a key role in income distribution and redistribution: market and state. The income components: market income, tax and government transfers issue respectively from those constituents. However, in Québec, inequality trends have not been examined enough using the contributions of those components. By focusing attention on economic cycles and their phases of recession and expansion over the past five years, those trends and contributions have not been examined enough. This is why we decided to analyze income inequality trends of economic families and unattached individuals in Québec during the period 1979-2004.