NOVELTY - The hydroprocessing system of hydrocarbon fuel has hydroprocessing zone (I) containing hydroprocessing catalyst and having inlet for co-currently receiving hydrocarbon feed (16) and hydrogen-containing gas phase (I), several additional hydroprocessing zones, and the separator for receiving product from final hydroprocessing zone and for separating the product into a hydrocarbon phase and recycled hydrogen-containing gas phase.    USE - For hydroprocessing of hydrocarbon fuel such as treatment of diesel, gas oil and naphtha such as hydrocracking of heavy hydrocarbon feedstock to lower boiling products, hydrocracking of distillate and higher boiling range feedstock, hydrogenation of aromatics, hydroisomerization, hydrodewaxing, and removal of metal from heavy streams.    ADVANTAGE - The hydroprocessing system is simple and compact, and enables efficient hydroprocessing of hydrogen fuel and suppression of sulfur content.    DETAILED DESCRIPTION - The hydroprocessing system of hydrocarbon fuel has hydroprocessing zone (I) containing hydroprocessing catalyst and having inlet for co-currently receiving a hydrocarbon feed and hydrogen-containing gas phase (I), several additional hydroprocessing zones, and the separator for receiving a product from final hydroprocessing zone and for separating the product into a hydrocarbon phase and recycled hydrogen-containing gas phase. Each additional hydroprocessing zones contain hydroprocessing catalyst and include a final zone and an upstream zone. The upstream zone has an inlet for co-currently receiving a hydrocarbon product from hydroprocessing zone (I) and recycled hydrogen-containing gas phase. The final zone has an inlet for co-currently receiving hydrocarbon product from the upstream hydroprocessing zone co-currently with hydrogen-containing gas phase (II).    DESCRIPTION OF DRAWING(S) - The figure shows the hydroprocessing system of hydrocarbon fuel.    reactor (14)    hydrocarbon feed (16)    gas (18)    product (20)    liquid gas separator (22)    hydrogensulfide-containing gas phase (24)    additional reactors (28,30)