In this paper, Artificial Bee Colony (ABC) optimization algorithm is proposed to solve nonlinear equation of Selective Harmonic Elimination pattern considering unequal direct current sources. Satisfying fundamental component and eliminating low-order harmonics are the objects of Selective HarmonicElimination switching pattern. A 7-level inverter fed by isolated unequal direct current sources is chosen for this study. The performance of ABC algorithm, which is 1 of the powerful and new evolutionary optimization patterns, is compared with particle swarm optimization, genetic algorithm, and bee algorithm used by other researchers. The comparison of results shows that ABC algorithm finds optimized switching angles with more accuracy and higher convergence compared with others. All aforementioned algorithms were run 30 times, and the statistical analyses show that the algorithm finds switching angles with higher accuracy and lower speed deviation than other algorithms. These comparisons are implemented in MATLAB software; furthermore, the experimental results are presented for the purpose of verification.