AbstractFew studies have investigated whether higher cardiorespiratory fitness (CRF) or favourable body composition are related to lower arterial stiffness in women. We therefore investigated the associations of CRF, body fat percentage (BF%), fat free mass index (FFMI), and mean arterial pressure (MAP) with arterial stiffness in 146 women aged 16–58 years. CRF was assessed by a maximal exercise test with respiratory gas analysis either on a cycle ergometer or a treadmill. Aortic pulse wave velocity (PWVao), augmentation index (AIx%), and MAP were assessed by a non-invasive oscillometric device and BF% and FFMI by a bioelectrical impedance or DXA device. CRF was inversely associated with PWVao (β = − 0.004, 95% CI − 0.005 to − 0.002) and AIx% (β = − 0.075, 95% CI − 0.102 to − 0.048) and these associations remained similar after adjustment for BF% or MAP, but not after the adjustment for age. FFMI was inversely associated with PWVao (β = − 0.010, 95% CI − 0.019 to − 0.002) and MAP directly associated with PWVao (β = 0.005, 95% CI 0.003 to 0.006) and AIx% (β = 0.092, 95% CI 0.069 to 0.116) and the associations with PWVao also remained after further adjustments for BF% and age. In conclusion, a higher FFMI and a lower MAP were independently associated with lower arterial stiffness.