Salophen modified biochar fibres derived from Luffa cylindrica sponges were prepared and subsequently studied as a potential U(VI) adsorbent by batch equilibrium experiments. The material was characterized before and after U(VI) adsorption by spectroscopic and microscopic methods of analysis. FTIR and SEM investigations revealed that the salophen modification of the biochar surface was successful without any significant changes of the textural properties of the material. The experimental data were well fitted by the Langmuir adsorption model (R= 0.99) and resulted in extraordinary high values for the maximum adsorption capacity even under acidic conditions (qmax at pH 3 and 5.5 equal to 714 g·kg-1 and 833 g·kg-1, respectively). Hence, the material could be a very attractive candidate as an effective adsorbent for the selective adsorption of U(VI) from process solutions and industrial wastewaters.