Abstract: A method is provided for designing robust multivariable digit controller of turbojet engine,in which the forwardback and feedback control structure is adopted in the divided flight envelope,the μ structurization is used to deal with the structured uncertainty and unstructured uncertainty,so that the problem for solving robust controller is transformed into standard H∞ control problem.The robust disturbance rejection and tracking performance is verified by simulation on a nonlinear model of the twin spool turbojet engine aerothermodynamics.