This paper is concerned with the adaptive control of sugar mill system and develops a controller based on indirect self tuning regulators in which the system parameters are identified using recursive least squares (RLS) method and the controller is designed using pole placement approach. The Sugar mill system is a linear multivariable system. Thus, designing a controller to overcome couplings and uncertainties such as external disturbances and parametric uncertainties is a critical problem. The most important novelty of this paper is using the disturbance rejection ability of self tuning regulators to overcome the coupling problem, since couplings are considered as disturbances in this paper. Simulation results are presented to verify the efficiency of the designed indirect self tuning regulator in the control of crushing mill machine. Moreover, the performance of the designed STR is compared with a sliding mode controller.