Background & aims: Malnutrition is a risk factor for development of pressure ulcers (PU). Nutritional supplementation may thus reduce the incidence of PU. We investigated the effect of nutritional supplementation on incidence of PU in hip-fracture patients at risk of developing PU. Methods: Hip-fracture patients (n=103) were included in this double-blind, randomised, placebo-controlled trial. They received 400 ml daily of a supplement enriched with protein, arginine, zinc and antioxidants (n=51) or a non-caloric, water-based placebo supplement (n=52). Presence and stage of PU were assessed daily for 28 days or until discharge (median: 10 days during supplementation). Results: Incidence of PU was not different between supplement (55%) and placebo (59%), but incidence of PU stage II showed a 9% difference (difference: 0.091; 95% CI: 0.07-0.25) between supplement (18%) and placebo (28%). Of patients developing PU 57% developed it by the second day. Time of onset (days) showed a trend (P=0.090) towards later onset of PU with supplement (3.6 ± 0.9) than placebo (1.6 ± 0.9). Conclusions: Hip-fracture patients develop PU at an early stage. Nutritional supplementation may not prevent PU at this stage, but contributes possibly to a delayed onset and progression of PU. Nutritional supplementation may be more effective if initiated earlier.