Since the 1980s, theoretical and applied artificial neural network researches have developed rapidly and gained great achievements in many fields. The main developmental courses of theoretical and applied researches in artificial neural network both at home and abroad in China are described. Emphases are put on the application of artificial neural network in many fields, such as mid-term and short-term weather forecasting, short-term climate prediction, agrometeorology, air pollution forecasting, recognition of satellite cloud images, meteorological observation data processing, and so on. Descriptions are further made on the recent researches on the key technology of modeling researches in weather forecasting using artificial neural network: over-fitting, network structure, fuzzy neural network (the combination of fuzzy system with neural network), and the weather forecast modeling of combining Genetic Algorithms with neural network.