PURPOSE: To compare the diagnostic accuracy between fine needle and large cutting needle biopies. METHODS & MATERIALS: Chest lesion was biopsied consecutively by 19 G or 22 G fine needle and 14 G large cutting needle with interval of 10-20 min. 119 patients confirmed by operation or clinical follow-up were evaluated. RESULTS: There were 65 patient confirmed as malignant lesion and 54 confirmed as benign lesions. Diagnostic accuracy was 87.7%(57/65) for malignancy and 85.2%(46/54) for benign lesion with fine needle. With large cutting needle, it was 90.8%(59/65) for malignancy and 88.9%(48/54) for benign lesion. In the benign lesion, specific diagnostic accuray was 48.1%(26/54) with fine needle, and 64.8%(35/54) with large cutting needle biopsy, respectively. Complications were hemoptysis(n=13, 10.9%), pneumothorax(n=7, 5.9%) and mild to moderate chest pain. Although, it is impossible to compare the complications by the two types of biopsy on same lesion, 10 cases of immediate hemopytsis and more severe chest pain occurred when large cutting needle biopsy was done. CONCLUSION: No significant difference in diagnostic accuracy between fine needle and large cutting needle biopsies was observed in malignant lesion. In benign lesions, larger sample volume may increase the chance of obtaining a specific diagnosis but has no influence on overall diagnostic accuracy of benignity. Thus, we believe that fine needle aspiration biopsy is an accurate, safe, and more tolerable means to be performed as first step for diagnosis of chest lesions.