Abstract: ObjectiveTo compare the clinical application of automatic biopsy needle and semiautomatic biopsy needle under CT guided lung biopsy. 
MethodsTwo hundred and fortytwo cases of percutaneous lung biopsy under CT guidance from March 2015 to October 2016 were performed in our hospital. Among them， 157 cases were performed with automatic biopsy needle （automatic group）， and 85 cases with semiautomatic biopsy needle （semiautomatic group）. The puncture success rate， sufficient specimen rate， diagnostic efficacy （accuracy， sensitivity and specificity） and the incidence of common complications were compared between both groups. 
ResultsThe puncture success rates were 1000％ in both groups. The sufficient specimen rate of the automatic group was 1000％ （157／157）， higher than 953％ （81／85） of the semi automatic group （P＜005）. The specificity and accuracy of the automatic group were 917％ （22／24） and （154／157）， higher than 917％ （22／24） and 981％ （154／157） of semiautomatic group （P＜005）. However， the sensitivity was 992％ （132／133） and 944％ （67／71） in the automatic group and the semiautomatic group （P＞005）. The incidence of needle bleeding was 338％ in automatic group， higher than 212％ of the semiautomatic group （P＜005）. There was no significant difference between incidences of pneumothorax， hemothorax， blood in phlegm， puncturerelated infection， air embolism and pleural reaction in both groups （P＞005）. 
ConclusionIn the operation of CT guided percutaneous lung mass puncture biopsy， two kinds of needle biopsy needles have the advantages and disadvantages， and only the applicable range is different. The automatic biopsy needle is sufficient with higher diagnostic accuracy and specificity. The semiautomatic needle biopsy needle has little risk of bleeding.

Key words: Lung cancer, CT guided percutaneous lung biopsy, Automatic biopsy needle, Semiautomatic biopsy needle