The parsing of non-projective dependency has been the bottleneck problem for the accuracy of dependency parsing system. There is extensive existence of non-projective dependency in Mandarin Chinese. Based on the U-penn Chinese Treebank,the paper investigates the distributions of edge-crossing dependency,an example of nonprojective dependency, in Mandarin Chinese. It is found that when edge crossings produced by clause sharing and circumposition are included,edge-crossing dependency can be found in 2849 sentences,about 16. 42 percent of the 15162-sentence corpus; when the range is limited to clauses,1712 sentences are identified,accounting for 11. 29 percent of the overall sentences; and apart from edge crossings caused by coordination,other usages can be divided into two categories with nine sub-categories.