Underwater local dry laser cladding (ULDLC) is a key technique for in-situ repair of nuclear power equipment. In this study, an underwater laser remelting technique is proposed to further enhance the wear resistance of duplex stainless steel (DSS) coatings fabricated by ULDLC. The effecets of laser remelting heat input on the microstructure and wear resistance of ULDLC-processed DSS coating were investigated. Results indicate that the microstructure of DSS coatings consisits of Widmanst?tten austenite (WA), intergranular austenite (IGA), grain boundary austenite (GBA), secondary austenite (γ2) and ferrite. With the increase of laser remelting heat input, the content of IGA and WA gradually decreases, while the ferrite content increases. After laser remelting, γ2 are eliminated and ferrite morphology transformed from flaky to equiaxed grian. Moreover, the microhardness of the remelted area increases to about 319 HV under optimal laser remelting parameters: a laser power of 3 kw, a laser spot diameter of 6 mm, and a laser scanning speed of 10 mm/s. The remelted zone exhibited enhanced microhardness increased by 25.7HV, with a 32% reduction in friction coefficient and 55% decrease in wear volume. The significantly improved wear resistance is attributed to the synergistic effects of surface oxide layer formation and δ-ferrite grain refinement.