Boilers and most boilers are classified as pressure vessels, and according to this article, they should not work at low pressure. If these tanks are working at low pressure, their efficiency will decrease and it will cause a drop in the quality of the output steam in the boiler. On the other hand, each of the steam applications require a certain working pressure and their maximum allowed working pressure is different. If the steam pressure entering the steam consuming equipment is higher than the working pressure, it may cause dangers. Therefore, it is very important and important to control the pressure of the boiler as accurately as possible. Since we are dealing with a non-linear and time-varying system, therefore, a control system must be designed that can handle this system well. Most of the proposed methods so far either do not have the ability to be realized physically or have considered the system to be very simple. Therefore, in this thesis, while modeling the boiler as accurately as possible and the relations governing its pressure, we will introduce an adaptive control system of the reference model with various uncertainties so that the uncertainty and inaccuracy of the model can be compensated. The simulation results prove the effectiveness of the proposed method in boiler pressure control.