Change of land use type in Lanzhou City from 1997 to 2009 is analyzed, and the ecosystem service value is counted in this paper. The results show that ecosystem service of Lanzhou is mainly for soil formation and protection, maintaining biodiversity, climate regulation. But the function of soil formation and protection, and the function of hydrological adjustment, has been declining since 1997, and because of blind expansion of built land and occupation of ecological land, the area of ecological land is reducing gradually in Lanzhou, which cause the ecological deterioration. The improved shuffled frog leaping algorithm is used to establish land optimization model, and the value of ecosystem services is chosen as its fitness function. Three kinds of optimization schemes, which are ecological, development and comprehensive benefit, are produced by this model. The optimized ecological system service value of Lanzhou City can reach 58.89×10⁸ yuan. In order to improve the value of ecological system service of Lanzhou City, the following suggestions is proposed: (1)The farmland should be transformed to forest and grassland reasonably, and the north south mountain's green transformation should be strengthened. (2) The farm land, grassland, garden land should be protected, and the expansion of the built land should be under control. (3)The farm land occupied by building should be compensated, and the better solution should be development of unused land which is available and exploring the potential of land use.