In the present paper, the production of laccase by Trametes versicolor (CBS 100.29) in laboratory-scale bioreactors, operating in semi-solid-state conditions, was studied. Three bioreactor configurations were investigated in order to determine the most suitable one for laccase production: immersion, expanded-bed and tray. In addition, the nature of support employed (inert or non-inert) on laccase production was also evaluated. According to the results attained in the previous work by our research group, nylon sponge and barley bran was employed as an inert and as a lignocellulosic support, respectively.Higher laccase activities were produced operating with barley bran than with nylon sponge as a support in all the configurations tested. As regards bioreactor design, the tray configuration led to the highest laccase activities especially operating with barley bran as a support, where activities of about 10-fold higher than that found in the corresponding cultivation with nylon sponge were attained. Therefore, it could be asserted that the tray bioreactor is a very appropriate bioreactor configuration to produce laccase by T. versicolor in solid-state conditions operating with lignocellulosic supports. [Copyright &y& Elsevier]