This research work will consist of mathematical modelling emphasizing HIV infection to human immune system including its responses to various available drug therapies. The main focus is to work on mathematical optimization and control on the models. It will enable us to administer an optimized level of therapies to AIDS patients and would thus be directly benefiting to the society. The objectives of the research work are three fold:i. to develop mathematical models associating HIV infection in human blood and the related treatment techniques, ideals of optimal control theory,ii. analytical and numerical studies of the fundamental mathematical models from control theory viewpoint andiii. to develop methods for determining optimal treatment based on model predictive controls.