The invention discloses application of a GSK-3beta inhibitor to in-vitro induction of human Breg cells and a method for inducing the human Breg cells in vitro by the GSK-3beta inhibitor. In the effects of inducing the human Breg cells in vitro by the GSK-3beta inhibitor and inducing transformation of common B cells into the Breg cells by the GSK-3beta inhibitor, the induction purity of inducing the Breg cells by the GSK-3beta inhibitor is high, secretion of Breg inflammatory cytokines is decreased after induction, and the Breg inhibiting function is enhanced after induction. By the method forinducing the human Breg cells in vitro by the GSK-3beta inhibitor, the operation is simple, a short time is consumed, the purity is high, the cell activity damage is high, the transformation efficiency is high, the cell activity is high, a source is wide, the pollution possibility is low, an insufficient amount of Breg in basic and clinical researches can be made up, and a novel experimental method is provided for further research on the Breg cells.