This study aims to evaluate outcomes of a community-based program to prevent suicide among the elderly (>or=65 years old) using a quasi-experimental design with two neighboring references. During 1999-2004, the program including depression screening and group activity was conducted by the public health nurses in the Minami district (population 1685) of Nagawa town, rural Japan. Pre-post changes in the risk of completing suicide were estimated by the incidence rate ratios (IRR). The risk for Minami's elderly females was reduced by 74% (age-adjusted IRR, 0.26; 90% CI, 0.07-0.98) more than the historical trend, while there was no change in the risk of Minami's males and nor in the male or female references. The local intervention using public health nursing would be effective against suicide for elderly females without diffusing to the surroundings.