Abstract: In this paper, the multivariable control problem on side-stream temperature of crude oil vacuum tower has been studied. In accordance with the characteristics of one-way connection between each side-stream, by building the temperature dynamic characteristics of each side-stream and the temperature dynamic characteristics between two adjacent side streams, multivariable predictive control system for side-stream temperature of crude oil vacuum tower has been designed. This control system has been successfully applied to a crude oil vacuum tower of a oil refinery, and shown its good performance.