This study evaluated the effects of Jerusalem artichoke (JA) and Lactobacillus plantarum singly or combined on growth, immunity and disease resistance of Pangasius bocourti. In the first experiment, different concentrations of JA (0, 5, 10, 20, 40, 80 and 160 g kg À1 ) were administered to determine an optimal concentration on growth of P. bocourti. In the second experiment, the optimal concentration of JA (5 g kg À1 ) was combined with 10 8 cfu g À1 L. plantarum. In the final experiment, five randomly selected fish from the second experiment were challenged with Aeromonas hydrophila. Treatments for second and third experiments were 0 g kg À1 JA (Diet 1), 5 g kg À1 JA (Diet 2), 10 8 cfu g À1 L. plantarum (Diet 3) and 5 g kg À1 JA + 10 8 cfu g À1 L. plantarum (Diet 4). Fish fed 5 g kg À1 JA or 10 8 cfu g À1 of L. plantarum significantly improved specific growth rate (SGR), feed conversion ratio (FCR), serum lysozyme activity and postchallenge survival rate (PCSR). Dietary in the combination of JA and L. plantarum showed significantly enhanced SGR, FCR, serum lysozyme, phagocytosis, respiratory burst activities and PCSR compared with control and individual applications. Dietary JA and L. plantarum significantly stimulated growth, immunity and disease resistance of P. bocourti.