[Background] Submucosal lesions are incidentally detected on barium meal study or endoscopy.The differential diagnosis of them includes a variety of neoplasms, inflammation, and extraluminal compression.Since conventional endoscopic biopsy is superficial, the diagnostic yield of submucosal tumors (SMTs) covered with normal mucosa remains low.Intraluminal biopsy is required for preventing dissemination and endoscopic ultrasound guided fine needle aspiration biopsy (EUS-FNA) has reported as effective modality.[Purpose] The purpose of this study is to evaluate the diagnostic yield of gastric SMTs using EUS-FNA.[Patients and methods] A total of 294 consecutive patients with gastric submucosal lesions were examined by EUS between 1997 and 2005.94 out of 294 cases underwent EUS-FNAB.The materials obtained from the EUS-FNA were stained with the rapid Romanowsky for cytological examination.Immunohistochemical staining was performed for the final diagnosis of GIST.[Results] Of the 294 cases, 115 were finally diagnosed by EUS: extraluminal compressions due to adjacent viscera were found in 32 cases and normal in 28, intraluminal lesions diagnosed as heterogenic pancreas in 40, lipoma in 7 and cyst in 8.The remaining 179 out of 294 cases were diagnosed as SMTs and 94 cases underwent EUS-FNA because of tumor size more than 2cm, patients request or malignant findings of EUS.The majority of SMTs examined with EUS-FNA was GIST (n=49), followed by spindle cell tumor (n=1 3), heterogenic pancreas (n=4), inflammatory tumor (n=5), gastric cancer (n=5), cyst (n=2), myogenic tumor (n=2), neurogenic tumor (n=2), carcinoid (n=1), Glomus (n=1) and unknown (n=10).The diagnostic yield of EUS and EUS-FNA in gastric lesions was 39.1% and 89.4%, respectively.[Conclusions] EUS-FNA is highly diagnostic in gastric SMT, particularly in patients with failure of previous EUS or endoscopic forceps biopsy to obtain a final diagnosis.