The maximum propionic acid (HPr) removal rate (R HPr ) was investigated in two lab-scale Upflow Anaerobic Sludge Bed (UASB) reactors. Two feeding strategies were applied by modifying the hydraulic retention time (HRT) in the UASB HRT and the influent HPr concentration in the UASB HPr , respectively. The experiment was divided into three main phases: phase 1, influent with only HPr; phase 2, HPr with macro-nutrients supplementation and phase 3, HPr with macro- and micro-nutrients supplementation. During phase 1, the maximum R HPr achieved was less than 3gHPr-CODL −1 d −1 in both reactors. However, the subsequent supplementation of macro- and micro-nutrients during phases 2 and 3 allowed to increase the R HPr up to 18.1 and 32.8gHPr-CODL −1 d −1 , respectively, corresponding with an HRT of 0.5h in the UASB HRT and an influent HPr concentration of 10.5gHPr-CODL −1 in the UASB HPr . Therefore, the high operational capacity of these reactor systems, specifically converting HPr with high throughput and high influent HPr level, was demonstrated. Moreover, the presence of macro- and micro-nutrients is clearly essential for stable and high HPr removal in anaerobic digestion.