Abstract: Flufenoxuron has very high insecticidal and ovicidal activity. It can prevent coleoptera, diptera and lepidoptera injurious insects from damaging maize, cotton, fruit, vegetable and soybean. It has been used in a great quantity for its characteristic of quick results, but can cause soil and water resource pollution. Therefore, it has an important value to monitor its concentration and develop monitoring instrument.Based on the mechanism that flufenoxuron can emit fluorescence in the ultraviolet light, a fluorescence fiber-optical measuring system is developed for monitoring its concentration. This system makes use of high-pressure mercury lamp as exciting light source. It combines with fiber-optical sensing technology to realize precise measurement of the concentration of flufenoxuron. Using this system to measure flufenoxuron's standard solutions,the fluorescence intensity has a linear relationship with the concentration in the concentration range of 0.050～1.000μg/ml.Because almost all the benzoyl urea pesticides(hexaflumuron and triflumuron,etc)by changing exciting and emitting filters and system configuration parameters.This fluorescence fiber-optical measuring system for measuring the concentration of benzoyl urea pesticides has several characteristics such as high sensitivity,wide linear range and low cost,etc.This research has established a good base for further improving the capability of domestic pollution detection and developing actual application of environment monitoring instruments.