Datum price of urban land is the important foundation, based on which the government conducts the macroscopic control and management of land price and guides land market.The datum land price can be divided into two catagories,i.e.single datum land price and integrated one.The former means the datum prices of urban land in the different uses such as commerce,housing and industry.The latter is an integration of the single datum land prices.The theoretical base for assessing integrated datum land price is the principles of the highest income and optimum use of urban land.It is feasible to integrate the datum land price based on william Alonso's rent-competed theory and the marginal analysis approach which is used to expound the spatial land allocation in urban area and its surrounding zone.A case study of assessing the integrated datum land price in a city in southern Jiangsu Province was outlined in this paper.