This paper, based on an analysis into the approaches, at home and abroad, of the conveyor belt joint monitoring, provides an in-depth investigation into the causes and conditions of the belt conveyor tension overload and fractures, finding that the fractures of the joint are random, and are among the most frequently occurring problems, along with steel-cordbelt conveyor belt deviation, drum slipping, roller life, fire, and the steel-cored belt longitudinal tearing etc Therefore, based on the fact that the joint length can be measured by detecting its tension with an senor, this paper investigates the technology of belt joint monitoring by means of the F-L curve,, so as to provide an early warning. This method the system practice shows that: the technology has good application value in production and application, has the vital significance to the enterprise safety production.