In this paper, an Enhanced Genetic Algorithm (EGA) based proportional integral-derivative (PID) controller is presented for control of nonlinear dynamic process. In EGA, the crossover and elite offspring are optimized using Ant colony Optimization (ACO) which improves the convergence characteristics and optimization capabilities of traditional Genetic Algorithm (GA).The proposed algorithm is implemented for closed loop control of Continuous Stirred Tank Reactor (CSTR) process. The performance of the proposed scheme is validated through the simulation results and by comparing with the conventional counterparts. The integral performance criteria viz., integral Square Error (ISE), Integral Absolute Error (IAE), Integral Time weighted Absolute Error (ITAE) of the EGA implemented CSTR system revealed a reduction of ISE equal to 1.5704e-4 at 50-150 sampling interval when compared to conventional GA. The results show that, EGA based nonlinear PID is more suitable for servo and regulatory operations.