本文研究模拟电路故障诊断中的定位理论和方法．电网络分担的理论和方法，伴随网络的理论和方法，分别被应用于故障定位中．文中还给出了另一种故障定位方法，这一方法是作者所提出的故障诊断定理的直接应用．在此基础上得出了两个诊断模拟电路故障的判据． This paper studies the theory and method of location in analog circuit fault diagnosis. The theories and methods of electric network sharing, along with the theories and methods of networks, are respectively applied to the fault location. Another method of fault location is also given in this paper. This method is the direct application of the fault diagnosis theorem proposed by the author. On this basis, two criteria for diagnosing the fault of analog circuit are obtained.