Artemisia capillaris (AC) extract was fermented with probiotic Leuconostoc mesenteroides MKJW, MKSR, Leu. mesenteroides KCTC 3719 (LM), and Leu. citreum KCTC3526 (LC), and their physiological effects were evaluated. Both MKJW and MKSR had the highest number of viable cells and metabolites, such as dextran, lactic acid, acetic acid, and mannitol, at 24 h fermentation. The fermentation metabolites were significantly correlated to strong α-glucosidase inhibition of MKJW and MKSR. MKJW fermented AC showed the highest α-glucosidase inhibition (76.05%), followed by MKSR (68.34%), LC (50.39%), LM (39.43%), AC extract supplemented with medium (CON1; 10.95%), and AC extract (CON2; −2.99%) at 24 h fermentation. The MKSR fermentation maintained intrinsic acetyl- and butyrylcholinesterase inhibitory activity of AC. Significant increase in antibacterial activity against tested ten foodborne pathogenic bacteria was found in ACs fermented by MKJW and MKSR compared to other fermented and non-fermented ACs. Our findings suggested that probiotic Leu. mesenteroides MKJW and MKSR could be used as probiotic starters in AC extract to improve multi-biological activities.