Abstract: The main problem existing in the practical applications of the pole-zero placement self-tuning liesin the heavy calculation which limits the sampling frequency of the systems.In this paper,on the basis ofthe pole-zero placement principle,a combined recursive self-tuning algorithm is proposed.Thisalgorithm,while retaining the original control characteristics,has greatly decreased its calculation task,and helps to raise the sampling frequency of the systems so to realize the adaptive control of the fast mov-ing scrvo systems.Different approaches to the deterministic system and stochastic system are discussed,and the application of the algorithm on an electrohydraulic servo system is presented in the paper.