This paper presents a model of the raw material homogenizing and mixing process in a cement plant as a multivariable stochastic system, and moreover proposes application of the extended horizon adaptive control (EHAC) with a static pre-compensator matrix with fixed parameters. The regulation and tracking performances of the hydraulic modulus (HM), silica modulus (SM), and iron modulus (IM) by the proposed control system are compared with the actually applied classical control method which is PI control with Smith compensators. The robustness performances of the extended horizon adaptive mixing control system are compared with the classical control, and also with a stochastic model reference adaptive control based on a one step prediction method, especially for changes of process dynamics including the dead time. The simulation results show that the proposed EHAC system has suitable performances.