Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently introduced automated biopsy gun simplifies core biopsies with increased quantity and quality of samples. Authors performed 38 percutaneous biopsies from 38 patients with 18G automated biopsy guns under US guide. Diagnostic target tissues were obtained in 33 biopsies (87%) inadequate tissues in 4 (11%), and adequate but not of target tissue in 1(3%). There was no major complication requiring treatment, but pain needing analgesics and pain with nausea / vomiting were experienced in 2 and 1 biopsies respectively. Average number of needle passes was 1.5(1-5) We concluded that US-guided gun biopsy was a easy and sage way to obtain tissue samples of good quantity and quality, especially useful in hospitals without constant availability of specialists in cytopathology.