Through this article, a numerical scheme based upon the modified fractional Euler method (MFEM) is introduced to find the numericalsolutions of linear and nonlinear systems of fractional differential equations (SFDEs) as well as nonlinear multi-order fractionaldifferential equations (MOFDEs). The fractional derivatives are defined by Caputo. The proposed algorithm is very simple and providesthe solutions directly without linearization, perturbations or any other assumptions. Illustrating examples with numerical comparisonsbetween the proposed algorithm and the exact and/or fourth order Runge Kutta method (RK4) are given to reveal the efficiency and theaccuracy of our algorithm.