Absorption chillers are the devices that required low grade thermal energy for instance waste heat of plant or renewable energy resources such as geothermal, solar etc. As absorption systems operate over lower coefficient of performance (COP) ranges therefore it is necessary to optimize the performance of these system. In this work, second law analysis and optimization of double effect series flow absorption chiller has been performed to improve its COP and energy efficiency. The dependence of these performance parameters on temperature of components has been assessed. Solution of the optimization problem using MATLAB has optimized the operating conditions which led to improvement COP nearly 10.25% and energy efficiency by 38.5%.