The authors use a self-built Chinese Discourse Treebank(80% relations are implicit) to recognize implicit relations. In this corpus, discourse relations are divided into three layers, the first layer has four types: causality, coordination, transition and explanation. Based on this corpus, maximum entropy classifier is employed to identify four types relations with context, lexical and dependency parse features. Experimental results show that total accuracy is 62.15% and the identification effect of coordination is the best, F1 reaches 75.26%.