The importance of exercise is evidenced by the 1996 publication of the Surgeon General's Report on Physical Activity and Health. All Americans, including the elderly, are encouraged to participate in regular physical activity. Because the senior population is growing, and seeks health services at higher rates than other age groups, the potential public health benefit of increased physical activity in this group is large. For several reasons, including senior's attenuated senses of balance and that ability to tolerate heat, the safety of the elderly while exercising should be considered. Helmet wearing is an important safety behavior as numerous communities have enacted policies requiring helmet use. This study, utilizing a 12-item survey, describes current bicycle helmet use among a convenience sample of bicycling seniors living in eight Mesa, Arizona based retirement communities. Participants were asked the number of days per week they typically rode their bicycles at least once, the usual duration of each ride in minutes, where they biked, whether or not they owned and wore a helmet, had they fallen or been hit by another vehicle while riding, the extent of any resulting injuries, as well as their age and gender. Descriptive and non-parametric statistics were utilized in the analysis of data. Results: Seventy-four females and 123 men completed the survey. The mean age was 70.7±7.2 years. Respondents biked an average of 4.9±2.3 days per week and averaged 40.5± 32.5 minutes of riding per day. Eighty-two participants (41.6%) reported owning a bicycle helmet and 55 (27.9%) wore a helmet on their most recent ride. Eighty-seven (44.2%) participants reported biking outside the retirement community and 25 (12.7%) reported falling or being hit by a vehicle within the past year. Chi-square analysis (X2=0.66; p<.05) indicated no differences in that likelihood of males or females wearing helmets. Those who rode outside the retirement communities (X2=22.6; p<.05) and those who had fallen or been struck by a vehicle within the past year (X2=5.81, p<.05) while riding were more likely to wear helmets than those not riding outside the retirement community and those who had not fallen or been struck by vehicles. Longitudinal studies are needed to validate these findings. Present data show that a small proportion of senior bicyclists wear safety helmets and that efforts to increase their usage are recommended. Keyword(s): adult fitness, physical activity, safety/injury prevention