During drilling often huge financial losses could incur due to severe drilling problems like lost circulation, pipe sticking, formation damage, high torque and drag. The major cause of these problems is the inefficiency of the drilling fluid in performing certain tasks that are dependent on its rheology. The control over rheology becomes more intricate due to the need of unexpected changing drilling conditions like temperature, pressure and types of formation. It is thus crucial to have drilling fluids knowledge enough to be engineered to suit particular conditions and be stable for wide range of operating conditions. Nanoparticles of two materials bentonite and ATR were tested in drilling fluids in small additive concentration and showed remarkable improvement in rheology. Rapid changes in viscosity and density were recorded that indicates the effectiveness of nanoparticles in drilling fluids for effective and versatile functionality. It is also understood that the stable nature of nanoparticles will inherit greater stability to the drilling fluids. Sufficient experimental results were generated by using different sizes and compositions of nanoparticles.