A diabetic foot ulcer is a common high-risk complication in diabetic patients, but there is still no universal dressing for clinical treatment. In this study, a novel dual-functional sulfated galactofucan polysaccharide/poly(vinyl alcohol) hydrogel (DPH20) is developed during freeze-thaw cycles. Experimental results indicated that DPH20 had a high specific surface area, a dense porous structure, and a good swelling property, which could effectively adsorb the exudates and keep the wound moist. Furthermore, DPH20 exhibited remarkably recruited macrophage capability and accelerated the inflammation stage by improving the expression of the mRNA of CCL2, CCR2, and CCL22 in macrophages. DPH20 could promote cell migration and growth factor release to accelerate tube formation under hyperglycemic conditions in cell models of L929s and HUEVCs, respectively. Significantly, DPH20 accelerates the reconstruction of the full-thickness skin wound by accelerating the recruitment of macrophages, promoting angiogenesis, and releasing the growth factor in the diabetic mouse model. Collectively, DPH20 is a promising multifunctional dressing to reshape the damaged tissue environment and accelerate wound healing. This study provides an efficient strategy to repair and regenerate diabetic skin ulcers.