Background/Aims: Treatment of gastric neuroendocrine tumors is determined by type and size of the lesion. This study aimed to compare the long-term efficacy of observation and endoscopic resection for type 1 gastric neuroendocrine tumors without metastasis. Materials and Methods: Among the 223 cases of gastric neuroendocrine tumors diagnosed between January 1996 and December 2011, 104 cases were type 1 gastric neuroendocrine tumors. Sixty-seven patients were treated endoscopically and 27 patients were observed without treatment. Endoscopic mucosal resection, endoscopic submucosal dissection, and polypectomy were the meth- ods used for endoscopic treatment. Therapeutic efficacy and rates of complication and recurrence were evaluated retrospectively. Results: In the endoscopic resection group, complete resection was observed in 53 patients (79.1%), and recurrence was observed in 14 patients (20.9%). On analysis of the observation group, no change was observed in 19 patients (70.4%), and tumor pro- gression was observed in 8 patients (29.6%). Median follow-up duration was 49 months (31∼210 months). No mortality was re- ported in either group during follow-up. Conclusions: Observation of type 1 gastric neuroendocrine tumors without metastasis yields results similar to those produced by endoscopic resection. Observation alone may be a safe treatment. (Korean J Helicobacter Up Gastrointest Res 2016;16:13-18)