A method for domesticating CHO-K1 cells into high-expression cells, comprising the following steps: culturing adherent CHO-K1 cells in a complete culture medium, to obtain log growth CHO-K1 cells; transferring the log growth CHO-K1 cells to a serum-
free medium for
suspension culture; performing a first liquid replacement
domestication, to obtain domesticated CHO-K1 cells; placing the domesticated CHO-K1 cells in a
chemically defined medium for
suspension culture; performing a second liquid replacement
domestication, to obtain domesticated suspended CHO-K1 cells; performing monoclonalization on the domesticated suspended CHO-K1 cells, to obtain CHO-K1
monoclonal cells; and screening the CHO-K1
monoclonal cells, to obtain high-expression CHO-K1
monoclonal cells. This method can domesticate CHO-K1 original parent cells into suspended cells, and screen cells having higher expression capability from the domesticated
cell population, thereby improving expression levels.