Purpose: The purpose of this study was to investigate the effects of sex education for the elderly on sexual knowledge and life satisfaction. Methods: A quasi-experimental study used a non-equivalent control group pre-post test design. A seven week sex education program for the elderly was developed and offered to the treatment group. Subjects were drawn from three welfare centers in Seoul. Twenty six were selected for the treatment l group while 27 were assigned to a comparison group. Sexual knowledge and life satisfaction were measured. Results: The level of life satisfaction reported by the treatment group was greatly increased (t=2.14, p=.037). There were no statistically significant differences in sexual knowledge between both the two groups. Conclusion: A positive influence of sex education was found to increase the level of life satisfaction. Further study on customized sex education for the elderly by individual characteristics is required.