Objective: To retrospectively analyze cases of surgically treated skull base chordoma,so as to summarize the clinical classification of this tumor and the surgical approaches for its treatment via transnasal endoscopic surgery.Methods: Between August 2007 and October 2013,a total of 161 patients(92 males and 69 females)undergoing surgical treatment of skull base chordoma were evaluated with regard to the clinical classification,surgical approach and surgical efficacy.Results: The tumor was located in the midline region of the skull base in 134 cases,and in the midline and paramedian regions in 27 cases(extensive type).Resection was performed via the transnasal endoscopic approach in 124 cases(77%),via the open cranial base approach in 11 cases(6.8%),and via staged resection combined with the transnasal endoscopic approach and open cranial base approach in 26 cases(16.2%).Total resection was achieved in 38 cases(23.6%); subtotal resection,86 cases(53.4%); partial resection of 80%-95%,29 cases(18%); and partial resection <80%,8 cases(5%).Conclusions: The clinical classification and surgical approaches adopted in this study seem suitable for transnasal endoscopic resection of skull base chordomas and may significantly improve the surgical efficacy of this method.