Optimum Unit Commitment (UC) is one of the most challenging tasks to the power system operator as it directly related to the generation cost. This motivates the researchers to formulate the optimization problem to minimize the generation cost by committing the generation units with satisfying total load demand. In this paper UC problem is formulated to minimize the total generation cost. Genetic Algorithm is applied directly using the toolbox available in MATLAB software. The results show that the GA Toolbox has capable to find the solution with lower time compared to program developed using m-file. Also it reduces the efforts and complications in program development. Also, the effectiveness of GA Toolbox is validated by comparing the results the various techniques available in the literature. The obtained results represent the reduction in total operating cost with satisfying all the constraints of the UC problem.