In this paper, a fast numerical algorithm based on the Taylor wavelets is proposed for finding the numerical solutions of the fractional integro-differential equations with weakly singular kernels. The properties of Taylor wavelets are given, and the operational matrix of fractional integration is constructed. These wavelets are utilized to reduce the solution of the given fractional integro-differential equation to the solution of a linear system of algebraic equations. Also, convergence of the proposed method is studied. Illustrative examples are included to demonstrate the validity and applicability of the technique. KEYWORDS convergence, numerical solution, operational matrix of fractional integration, Taylor wavelets, weakly singular integro-differential equations Math Meth Appl Sci. 2019;42:4427-4443.wileyonlinelibrary.com/journal/mma