SummaryFor an elementary study in vitro of probiotics with aid of antioxidant property for ameliorating oxidative stress, Lactobacillus pentosus subsp. FS4722, Lactobacillus plantarum subsp. FS5062, FS5382 and FS5498 were used to evaluate their antioxidant property via chemical‐based and cellular assays. A significant dose‐dependent manner was observed in the results of DPPH, ·OH and ·O2− radical‐scavenging activity. Principal component analysis (PCA), however, showed that the total antioxidant activity of four Lactobacillus was positively associated with their ability against H2O2‐induced HepG2 cell death, which indicated Lactobacillus pentosus FS4722 (95.07 ± 5.08%) had great potential for repairing oxidative damage in HepG2 cells oxidative stress model. The potential regulatory pathway of Lactobacillus FS4722 antioxidant action is reduction of intracellular ROS levels, improvement of SOD and CAT enzymes activities along with the activation of Nrf2 signalling and upregulation of the transcription levels of antioxidant factors NQO1, GCLG, GCLM and HO‐1.