Purpose <p>Carotid–femoral pulse wave velocity (cfPWV), an index of arterial stiffness, is one of the earliest indicators of cardiovascular risk. Studies of adolescents with anorexia nervosa have demonstrated increased arterial stiffness compared to healthy controls. Little information is available on the effect of weight restoration on arterial stiffness in adolescents with anorexia nervosa.</p> Methods <p>This pilot longitudinal study examined changes in arterial stiffness during weight restoration in adolescent females admitted to an inpatient eating disorder unit. Female adolescents aged 15–19 years with a diagnosis of anorexia nervosa and a body mass index (BMI) &lt; 85% of median BMI for age and sex, were recruited from consecutive eating disorder admissions at Westmead Hospital, Australia. Weekly measurements of cfPWV were performed for up to 4 consecutive weeks.</p> Results <p>12 participants were included, with an average follow-up of 3.2 ± 1.1 weeks. Using mixed-effects models, we observed a significant increase in BMI (95% CI 0.60, 0.80; <i>p</i> &lt; 0.01) along with a modest but statistically significant decrease in cfPWV. The rate of change in cfPWV observed was −&#xa0;0.2 m/s per week (95% CI −&#xa0;0.37, −&#xa0;0.03; <i>p</i> = 0.03). Mean arterial pressure (MAP) was significantly associated with cfPWV (<i>p</i> &lt; 0.01). There was a borderline association between cfPWV and BMI (<i>p</i> = 0.05).</p> Conclusions <p>Our findings suggest a possible reduction in arterial stiffness with weight restoration, although results must be interpreted with caution due to the small sample. Nevertheless, serial measurements of cfPWV in this population are feasible, supporting the need for larger longitudinal studies in this population.</p> <p><i>Level of evidence</i>: Level III.</p>