Abstract: Objective To study the application value and safety of percutaneous coaxial-core needle biopsy via director assisted CT guidance in retroperitoneal lymphomas. Methods From June 2013 to May 2015， a total of 18 patients with retroperitoneal masses couldn’t undertaking surgercal biopsy were enrolled in this study. The 18 patients received percutaneous coaxial-core needle biopsy via director assisted CT guidance. At least five biopsy samples from different position were taken for pathology and immunohistochemistry examination. A dosage of 10-30 mg of cisplatin was injected into the lesion by trocar needle. Results Of the 18 patients underwent percutaneous coaxial-core needle biopsy via director assisted CT guidance. The success rate of puncture and biopsy was 100％. Operation time was 20-40 min （average 30 minutes）， and 5-9 sequence with 45-90 pictures of scan were used. No complications such as hemorrhage and pneumothorax occurred. Ten cases of retroperitoneal lymphomas were diagnosed， among whom there were 6 cases of diffuse large B lymphoma， 2 cases of follicular lymphoma and 2 cases of lymphoid cell lymphoma. According to Ann Arbor stage，there were 2 of stage Ⅱ， 6 of stage Ⅲ， and 2 of stage Ⅳ. The combination of chemotherapy and radiation was performed on lymphoma patients. Conclusion Percutaneous coaxial core needle biopsy via director assisted CT guidance with minimal invasiveness and fewer complications is a safe and effective minimally invasive technology， worthy of clinical application in the diagnosis of retroperitoneal lymphoproliferative disease.