The main aims of this study are to examine the income disparities’ evolution among the West-African Economic and Monetary Union (WAEMU) countries over the period 1980-2019, and to determine whether the reforms implemented in the region since 1994 have helped to reduce or to accentuate the income disparities among the Member States of the Union. The approach used for the analysis is that of sigma-convergence. It consists in studying the evolution of income dispersion over time, standard deviation being generally used as measure of dispersion. The results obtained show a reduction of per capita income inequalities among the WAEMU Member States. They also point out that the reforms undertaken in the area since 1994 have partly helped to reduce the income disparities among nations. In view of these findings, the study recommends to the community authorities to continue the implementation of the reforms and to reinforce the coordination as well as the harmonization of economical, financial and commercial policies of the Union