PI or PID based control system are widely used in control process industries because of their implantation is simple and they assure acceptable performance for industrial processes and their can be tuned manually by industrial operators. However, these controllers provide better performance only at given set of operating range and they need to be redefine if there is change in operating conditions. Further, the conventional controller performance is not up to the expected level for nonlinear and dead time processes. In the present industrial scenario, all the processes require automatic control with good performance over a wide operating range with simple design and implementation. This provides us the motivation for development of Fuzzy logic based process control system which can control process efficiently for all practical operating conditions. The fuzzy logic has been used to control the air pressure in the vessel using matlab as programming platform and the results are compared with that PID control. It has been demonstrated that fuzzy logic based control system is more accurate than the PID control system.