In vitro anti-obesity effects of anti-cancer (AC) functional kimchi in differentiated 3T3-L1 adipocytes were studied. We constructed three experimental groups: Control, standardized kimchi (SK), and AC functional kimchi (A-FK) that included active ingredients and Lactobacillus plantarum. Kimchi extracts did not show any cytotoxicity in pre-adipocytes in the concentration range of 1 – 5 mg/mL. A-FK significantly reduced fat droplet formation and absorbance in differentiated 3T3-L1 adipocytes, as shown by Oil red O staining, compared to Control and SK (P < 0.05). SK and A-FK reduced adipo-/lipogenesis related genes such as C/EBPα, SREBP-1, LPL, and LXRα compared to Control (P < 0.05). Especially, AFK more greatly reduced SREBP-1 and LPL compared to SK (P < 0.05). A-FK up-regulated the β- oxidation related gene CPT-1c and down-regulated the pro-inflammatory cytokine IL-6 compared to Control (P < 0.05). Based on the results, A-FK exhibited anti-obesity effects by inhibiting fat droplet formation and adipo-/lipogenesis related genes by regulating the β-oxidation related gene CPT-1c and pro-inflammatory cytokine IL-6. In previous studies, A-FK kimchi already exhibited a strong anti-cancer effect. These results indicate that A-FK increased anti-obesity activity in this model system due to its functional ingredients and anti-cancer functionality.