Abstract: From April to May 2000, we investigated the number of Siberian crane and environment condition at their stop-over site in Momoge Nature Reserve. The Siberian cranes arrive at Momoge Nature Reserve on about April 3 and leave on May 8. The period of stop-over is 36 days. Most of the cranes arrive here during the end of April, and the largest number reaches 577 individuals on April 27. The activity of cranes is affected by weather condition, such as wind velocity, temperature, and rainfall. Most cranes are distributed in wet meadow, shallow water and at Hanqian in the middle of ponds. They mainly feed on plants, and also on fish in this area. We offer some recommendations for measures for research and conservation of Siberian crane.