The present article reports on the design, modeling and parametric optimization of a thermoelectric cooling system for electronics applications. An analytical model based on energy equilibrium is developed for cooling a microprocessor using a thermoelectric module with an air-cooled finned heat sink. The proposed analytical model is validated by experimental measurements and by comparison with detailed 3D numerical simulations. Estimation of effective material properties of the thermoelectric module using manufacturer-reported performance characteristics is found to reduce the uncertainty in the calculation of module input power as compared to experimental measurements. A parametric optimization of the thermoelectric module and heat sink is carried out to maximize the coefficient of performance (COP) and achieve the required cooling capacity of the microprocessor. The effectiveness of the proposed methodology is demonstrated for cooling current high power microprocessors. At a constant input current, the cooling capacity and COP of the thermoelectric cooling system increase with increasing thermoelectric module geometric ratio. Furthermore, at a constant geometric ratio, the cooling power increases with increasing input current to reach a maximum value and then decreases. The present study highlights the importance of designing and fabricating high-performance thermoelectric cooler modules with optimum parameters for cooling specific electronic components. The results indicate that the cooling capacity can be increased by ~70% using thermoelectric modules with optimized parameters as compared to using non-optimized commercially available thermoelectric modules.