Knowledge discovery is an important part of reservoir management, and it is also a bottleneck of widespread application of knowledge. So we should make use of some particular data mining methods to discover knowledge, which should be based on some particular fields. According to demand of oil and gas development and characters of reservoir data set, puts forward a new idea of knowledge discovery in reservoir management by the technology, such as data cleaning, data mining, knowledge evaluation, visualization, and illuminates the approach for its implication by the experiment.