Objective To use bioelectrical impedance vector analysis (BIVA) in a cohort of systemic sclerosis (SSc) patients in order to assess their nutritional status in comparison to other groups of patients and to find any correlation with clinical characteristics and outcome of the disease. Methods We retrospectively collected data from 50 SSc patients who underwent BIVA for clinical suspicion of malnutrition, and compared them with patients affected by other chronic autoimmune rheumatic diseases (OCAD, n.27) or only symptomatic (n.15), and with 50 healthy controls (HC). Results SSc patients presented significantly lower values of phase angle (PhA), basal metabolic rate (BMR), body cellular mass (BCM) and an increase in extracellular water (ECW) (p<0.01 for all) than HC, unlike body mass index (BMI). No significant differences were found between SSc and OCAD. Among SSc patients, age directly correlated with ECW (ρ=0.342; p=0.015) and inversely with PhA (ρ=-0.366; p=0.009). Female sex, anaemia, hypoalbuminemia, reflux and early satiety/abdominal distension associated with relevant alterations in BIVA results. BIVA parameters were significantly different when cardiopulmonary and microvascular involvement was present. Four patients died during the study: they had significantly (p≤0.01) lower PhA, BMR and BCM, with an increased ECW. Conclusion BIVA, unlike BMI, allowed an accurate characterization of SSc patients at risk of malnutrition, correlating with serological malnutrition markers, with SSc-specific organ manifestations (cardiopulmonary involvement and microvascular damage) and with mortality. BIVA parameters might represent a surrogate marker of damage accrual that leads to malnutrition, thus playing a leading role in the prognostic stratification of SSc patients.