The aim of this study was to describe resting pulse rate and associated factors among adolescents. This was a cross-sectional analysis nested in a prospective cohort study, including 4,452 adolescents born in Pelotas, Rio Grande do Sul State, Brazil in 1993, representing 87.5% of the original cohort. Pulse rate was measured with an electronic device at the beginning and end of the interview, and the mean value was used in the analyses. Mean pulse rate was 78.4bpm (SD = 11.0) in the total sample, 76.5bpm (SD = 10.7) in boys, and 80.2bpm (SD = 10.9; p < 0.001) in girls. Black adolescents showed lower mean pulse rates. There was a direct association between pulse rate and blood pressure. Physical activity was inversely associated with pulse rate in the crude analysis only. Elevated pulse rate is strongly associated with high blood pressure, and both variables are predictors of risk of chronic disease in adulthood.