Abstract: Nowadays issues of various fault types and difficult diagnose restricted the improvement of economic benefit andsystem efficiency of progressing cavity pump（ PCP） production system. Thus an analytic hierarchy fault diagnosis method for PCP wellis put forward, combing the analytic hierarchy process with fuzzy mathematics theory. This method establishes appraisal index system,constructs hierarchical structure, judgement matrix and membership function for some fault, so the appraisal value of this fault canbe obtained. Contrasting the appraisal values of different PCP well fault can determine the true fault of PCP well. Actual applicationproved that the method has certain accuracy. This has guidance meaning for the fault diagnosis and system efficiency improvement ofPCP well in the oil field.