This paper analyzes the main influential factors on producer services agglomeration in Yangtze River delta urban agglomerations using panel data for 16 cities from 2007 to 2011.It is shown that the degree of industrial development and information technology has significant promoted producer services agglomeration;Knowledge intensity will be in positive relation to the agglomeration except financial industry;contrary to the hypothesis,the actual use of foreign capital has the negative effect on the agglomeration;the size of population has major influence on it except the business services and scientific research;the size of government has only a weak negative impact on the transportation,storage and postal industry.