The invention provides a method, apparatus and system for detecting faults in an NFV system. Faults in the NFV system can be effectively located by the method, and the fault locating efficiency can be improved by the method. In the method, a detection proxy apparatus receives position information of a monitoring point on a business path sent by a detection control apparatus, and the detection proxy apparatus is located in the NFV system; the detection proxy apparatus obtains information for locating faults from the monitoring point according to the position information of the monitoring point, the information for locating faults is information obtained by the monitoring point according to filtering conditions, and the information for locating faults comprises the position information of the monitoring point; and the detection proxy apparatus sends the information for locating faults to the detection control apparatus. The detection control apparatus can determine the faulty monitoring point according to the information for locating faults and a business model corresponding to the business path.