The　petroleum　and　the　chemical　engineering　equipments　were　broken　increasingly　under　the　rigorous　working　condition　of　the　hot　corrosion.　Nickel-based　cored　wire　was　sprayed　to　surface　of　Q235　steel　to　resist　hot　corrosion.　The　hot　corrosion　behavior　of　NiCrMo　coatings　by　oneself　research　to　manufacture　in　the　salt　corrosion　at　750　degrees　C　were　studied,　compared　with　the　performance　of　the　material　Q235　steel.　Metallographical　microscope　and　SEM　were　used　to　observe　the　morphology　of　the　corrosion　products　and　X-ray　diffraction　was　used　to　determine　the　phase　structures.　Results　show　that　when　nickel-based　cored　wire　which　contains　the　certain　content　of　Ni,　Cr　and　Mo,　is　sprayed　to　surface　of　Q235　steel,　can　become　the　oxidized　film　to　protect　coatings　and　raise　the　performance　material　Q235　steel　to　resist　the　hot　corrosion.　NiCrMo　coatings　have　superior　function　of　resist　hot　corrosion,　is　suitable　for　use　in　the　protection　material　of　the　petroleum　and　the　chemical　engineering　equipments.