This study assessed the effectiveness of three intervention strategies to improve the participation rate of gastric cancer screening among people who had never undergone such screening, and those who had been screened for the disease, but not recently. It was conducted in the Ilsandong-gu District of Goyang City, Korea. The population for the current study was restricted to male residents, aged 40-65 years, who received an invitation letter to undergo gastric cancer screening from the National Health Insurance (NHI) Corporation at the beginning of 2010. The subjects were divided into two categories according to their screening history: never-screened, and ever-screened. A total of 2,065 men were eligible: 803 never-screened and 1,262 ever-screened. In each screening category they were randomly assigned to one of three intervention groups: 1) tailored telephone counseling; 2) tailored postcard reminder after tailored telephone counseling;and 3) tailored telephone counseling after tailored postcard reminder. At 3 months post-intervention, never-screened men with any intervention were more likely to undergo gastric cancer screening (OR=2.75, 95% CI: 1.22-6.18) compared to those in the reference group (no intervention). However, there was no statistically significant intervention effect in ever-screened men (OR=1.21, 95% CI: 0.65-2.27). Examination of the intervention effects by intervention group among never-screened men showed that those in the postcard reminder after telephone counseling group to be statistically significantly more likely to undergo gastric cancer screening (OR=4.49, 95% CI: 1.79-11.29) than the reference group (no intervention). Our results highlight that use of tailored postcard reminders after tailored telephone counseling is an effective method to increase participation in gastric cancer screening among men who had never been screened.