We investigated the effect of Sanhuang ointment on the indwelling time and vein injury repair in patients receiving intravenous infusion via peripheral venous indwelling needles. Patients (n=120) who received infusion via peripheral venous indwelling needles were randomized into Sanhuang ointment, Hirudoid and blank control groups. The indwelling time, venous injury and repair rate, venous intimal roughness rate, vascular wall thickening rate, thrombosis rate and blood flow velocity were compared within 24h and on day 4 post-needle removal. The indwelling time in the Sanhuang ointment group was 7 (6,8) days, significantly longer than that in the Hirudoid (5(4,6) days) and blank control groups (4(3,5) days) (P0.05). On day 4, the rates of venous intimal roughness, vascular wall thickening and thrombosis were significantly lower, while the blood flow velocity and venous repair rates were significantly higher in the Sanhuang ointment group than those in the Hirudoid and blank control groups (P<0.05). Sanhuang ointment application extends peripheral venous indwelling time and promotes vein repair without increased injury risk.