Behavioral model is an effective tool to design nonlinear radio frequency and microwave circuits. Using accurate behavioral model, engineers can greatly reduce circuit development time by eliminating the need to build expensive and time-consuming hardware prototypes. At present, noise modeling of low noise amplifiers (LNA) mainly focuses on equivalent model, while relatively little research has been done on behavioral model. Therefore, this paper will study the behavioral model of the the LNA. It includes the theoretical derivation of the noise parameter testing process of the LNA, the extraction and the verification of the behavioral model of the LNA in simulation.