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Aiming at the increasing threat of space debris to spacecraft, on the basis of clear research methods of space environment, analyze the research status of long-term evolution model of space environment at home and abroad. Taking LEGEND model and DAMAGE model as examples, study the mechanism of the foreign space environment’s long-term evolution model, put forward the key scientific problems of long-term evolution model, and introduce the research status. Forecast the future research direction of long-term evolution model.