This study evaluated the antioxidant and skin-whitening activity of fermented Lindera obtusiloba flower extracts and optimized the fermentation process. First, the antioxidant capacity was measured. In the DPPH assay, one strain increased the antioxidant capacity after 24 h of fermentation, and in the ABTS assay, three strains increased the antioxidant capacity after 24 h of fermentation. The TPC and TFC assays both revealed an increase in the extraction of phenolic compounds in three strains after 24 h of fermentation. Then, experiments using B16F10 cells were conducted to determine the whitening activity. No cytotoxicity was observed for the fermented flower extract in the concentration range of 12.5–100 μg/mL. Meanwhile, treatment with the fermented extract at 100 μg/mL resulted in a 34.7 ± 0.9% reduction in melanin production and a 34.2 ± 1.8% reduction in tyrosinase production versus the values before fermentation (both p<0.05). Thus, the results confirmed that fermentation of L. obtusiloba flowers can enhance their whitening effect.