This research deals with design and simulation of incremental conductance variable step size method in maximum power point tracking for standalone PV system. MATLAB SIMULINK and MATLAB programming are used to model all parts of this system. Designation parameters verified with the simulation values. Finally, the results are compared in the cases of fixed and variable step size. Proposed method is not only more accurate and faster, but also it is more efficient in comparison with its conventional method (fixed step size). Output results are figured in the last chapter which can prove these purports.