GDP（Gross Domestic Product）is an important indicators to measure a country’s or a region’s economic output and development level. However，the traditional GDP does not accurately reflect the negative impact of economic growth on the environment and resources，can not reflect the overall progress of society too. As well as China’s economic development is at the expense of environment，etc，therefore，environmental and ecological factors must be included in GDP accounting system. On the basis of the understanding of urban green GDP，this paper analyzes the necessity of urban green GDP accounting，discusses a kind of reasonable urban green GDP accounting method，expounds the relations between urban green GDP and economic sustainable development.