Purpose: The purposes of this study were to describe the prevalence of low weight and to investigate related factors contributing to low weight in community-dwelling older adults. Methods: From the database of the Fourth Korean National Health and Nutrition Examination Survey (KNHANES-IV), the researchers selected 2,964 older adults aged over 65. The original study was a population-based epidemiological survey of health and nutrition with a stratified multistage clustered probability design. Data were analyzed using x2-test and multiple logistic regression with the SPSS/WIN 18.0 program. Results: The prevalence of low weight in older adults was 4.7%. The prevalence of low weight was different according to demographic characteristics. That is, the rate was higher in male elders, older ones, and rural residents. In the cases of current smoking, frequent alcohol consumption and no chronic disease, the prevalence of low weight was higher. Age, gender, area of residence, and current smoking were found to be contributing factors to low weight in community-dwelling older adults. Conclusion: The result of this study provides important insights into possible reasons for low weight in community- dwelling older adults and suggests that low weight should be considered in promoting older adults` health.