In recent years，some engineering cases showed that the protection effect of epoxy zinc-rich coatings on bridge deck was not ideal，especially premature corrosion damage would occur for long-span steel bridge deck in the south coast. The main reason is that the zinc powder fails due to the reaction with water and gas in high humidity and high temperature environment. On the other hand，the zinc-rich coating is prone to slip with substrates and intermediate layer under vehicle pressure for its high pigment volume concentration（PVC），high brittleness and weak penetration ability. In this paper，a high toughness non-zinc heavy-duty coatings was prepared using tough epoxy resin，toughening agent and flexible curing agent. Its mechanical and anticorrosive properties were studied through tensile tests，heat-resistant salt water immersion tests，salt spray tests and high-temperature adhesion tests. The results showed that the high toughness non-zinc heavy-duty coatings prepared by polyurethane toughened modified epoxy resin（SLpu）， low molecular weight polyurethane modified epoxy resin toughening agent（Dslu）and composite curing agent［m（polyether amine curing agent T）∶m（flexible curing agent F）=5∶1］had excellent tensile performance，salt spray resistance，and heat-resistant salt water performance. In particular，the heat saltwater resistant performance far exceeded that of epoxy zinc-rich coatings，making it more suitablefor the protection of long-span steel bridge deck pavement systems in southern coastal withhigh humidity environments. It has certain reference significance for solving the problem ofinsufficient service life of steel deck protection systems at present.