Abstract: Explore the use of the planthoppers adult worms the plexus rate estimation methods and means of the adult population density. Based on the the planthoppers adult population of field survey data, population density (y) and insects plexus rate (x), respectively, fitting the exponential function, power function, a quadratic function, a cubic function, linear and logarithmic function 6 kinds of different models. The results showed that the highest estimation accuracy of a cubic function method, the error is small, and the application of the best and average population density and insects plexus rate (x) Fact Sheet (y) the optimal mathematical model. Optimal mathematical model fitting can be applied in the production of monitoring the occurrence of the field planthoppers adult.