Purpose – The purpose of this paper is to develop a new method based on operational matrices of twodimensional delta functions for solving two-dimensional nonlinear quadratic integral equations (2D-QIEs) of fractional order, numerically. Design/methodology/approach – For this aim, two-dimensional delta functions are introduced, and their properties are expressed. Then, the fractional operational matrix of integration based on two-dimensional delta functions is calculated for the first time. Findings – By applying the operational matrices, the main problem would be transformed into a nonlinear system of algebraic equations which can be solved by using Newton’s iterative method. Also, a few results related to error estimate and convergence analysis of the proposed method are investigated. Originality/value – Two numerical examples are presented to show the validity and applicability of the suggested approach. All of the numerical calculation is performed on a personal computer by running some codes written in MATLAB software.