In this paper, new technologies and algorithms such as machine learning and swarm intelligently optimize algorithm are introduced into the condition monitoring of wind turbines, and the method of temperature trend analysis is used to monitor the condition of wind turbines. Firstly, in order to solve the problems of slow convergence speed and easy to fall into local optimum during the training of wavelet neural network, an improved method of Flower Pollination Algorithm optimized wavelet neural network is proposed, and the temperature model of wind turbine is established, and the model is used to carry out temperature prediction, and then the state of the wind turbine is obtained by analyzing the temperature residual, so as to achieve the purpose of online temperature monitoring.