Analysis on the ecosystem service value change in Dalai Lake Natural Protection Area. The ecosystem service value of Dalai Lake Natural Protection Area in the year of 1999 and 2007 were analyzed using market value method,shadow engineering method,opportunity cost method,wildlife judicial price method and etc. The ecosystem service value of Dalai Lake Natural Protection Area was 353. 28 * 108 Yuan in the year 1999. The ecosystem service value decreased by 28. 66% from the year 1999 to 2007. In the changed value of each ecosystem service,the value of controlling water,material production and biodiversity had sharply declined. The reason of ecosystem service value decreasing in Dalai Lake Natural Protection Area was due to reduced water area and grassland degradation caused by climate change and human activity.