The invention discloses a method for generating a suboptimal supervisory controller of a discrete event system. The method comprises the following steps of 1, constructing an automaton model PLANTi= (Qi, sigma i, delta i, qi0, Qim) of each component Gi in the system, wherein Qi, sigma i, delta i, qi0 and Qim are a state set, event set, transfer function, initial state and identity state set of the ith component respectively, and calculating a global automaton model PLANT of the system; 2, converting performance indexes E described by characters into an automation model SPECA0 of the performance indexes E; 3, calculating an event set DAT and an uncontrollable event weight DATu when each state of the performance indexes E is forbidden; 4, calculating an adjacent controllable event set J (sigma) corresponding to each uncontrollable event sigma and an event set sigma defined with sigma at the same time in the automaton model PLANTi of each component Gi; 5, obtaining a set delta formed by the transfer functions of the automation model SPECA0 of the performance indexes E; 6, generating the suboptimal supervisory controller of the discrete event system according to the set delta formed by the transfer functions of the automation model SPECA0 of the performance indexes E. Through the adoption of the method, the suboptimal supervisory controller of the discrete event system can be generated according to the performance indexes.