<title>Abstract</title> Parks are one component of the built environment to promote regular physical activity (PA) among youth. This study investigated differences in park-based PA among youth based on demographics and park features in racially/ethnically diverse communities. In 2017-2018, parks were selected in majority Asian (n=3), Latino (n=5), and Black (n=4) neighborhoods in North Carolina (n=6) and New York (n=6). Researchers recruited parents/caregivers of 5–10-year-olds to participate. Children wore an Actigraph GT3+ waist accelerometer and a QStarz GPS unit and were instructed to play normally for at least 15 minutes. Evenson cutpoints were used to classify PA levels as sedentary, light, moderate, and vigorous. Chi-squared tests and non-parametric Kruskal-Wallis tests were used to examine differences in PA intensity minutes (sedentary, light, moderate-to-vigorous) across study location and demographic variables. Youth participated from NY (n=200) and NC (n=157). Overall, most park-based PA was spent in light intensity (59.9%), followed by moderate-to-vigorous intensity (32.4%). Females, compared to male participants, spent more time in sedentary behavior (9.0%, 6.1%) and less time in moderate-to-vigorous PA (26.6%, 38.1%). Participants who identified as Black (32.9% MVPA), Latino (35.8%), and Other (39.8%) spent higher percentages of time in moderate-to-vigorous PA than Asian (26.6%) and non-Hispanic White (21.3%) participants. The highest proportion of moderate-to-vigorous PA occurred on swing sets (46%) and basketball courts (45%). Racial/ethnic, sex, and activity area differences in park-based PA indicate that diverse youth use parks uniquely; these factors should be considered in designing parks for various ages and backgrounds.