Falls is a geriatric syndrome that often occurs in elderly. Falls can cause by several factors, such as physical condition, family behavior and the environment around elderly. This research means to investigate the correlation between family knowledge and behavior regarding fall prevention with risk of fall in the elderly. This research used cross sectional design with 57 samples of family with elderly (>60 years-old) in Pondok Karanganom, Klaten. Result shows that the knowledge level of family is in good category (100%), while family behavior is grouped into poor (90%), average (15.8%) and good (84.2%). The risk of falls among elderly categorized into high (36.8%), low (33.3%) and no risk (29.3%). Correlation score between family knowedge and fall risk is 0.133 (p value 0.323< 0.05), while correlation score between family behavior and elderly risk fall is 0.340 (p value 0.01 < 0.05). This reseacrh is another evidence that knowing is not doing and nurse should provide comprehensive assessment and intervention in managing risk of fall in the elderly.