Abstract: Taking Dendrobium officinale produced in Changle Forest Farm, Yuhang District, Hangzhou City, Zhejiang Province as the research object, this study investigated the efficacy of polysaccharide extracts from its stems in terms of in vitro antioxidant activity, cytotoxicity, proliferation-promoting effect, moisturizing property, scratch wound healing and protection against H₂O₂-induced damage. The results showed that the polysaccharide extract of D. officinale exhibited excellent antioxidant activity. The extract of 1.00 mg·mL^-1 scavenged 61.44% ± 0.64% of DPPH free radicals. Moreover, compared with the control group without polysaccharide extract, the addition of 1.00 mg·mL^-1 polysaccharide extract significantly promoted the proliferation of HaCaT cells and moisturizing effect, with a relative proliferation rate increasing by 96.05% ± 10.95% and the repair rate for dry damage reaching 83.92% ± 6.16%. HSF cells incubated with the polysaccharide extract exhibited obvious protective effect against H₂O₂ stimulation, with a cell viability of up to 91.07% ± 5.97%. These findings indicate that the polysaccharide extract of D. officinale possesses strong antioxidant, moisturizing and repairing effects, is mild and safe, and has potential for development as a cosmetic raw material.