A primary cell culture medium for culturing primary lung cancer epithelial cells, containing an MST1/2 kinase inhibitor, a ROCK inhibitor, fibroblast growth factor 7, at least one additive of B27 additive and N2 additive, hepatocyte growth factor, insulin-like growth factor 1, interleukin 6, and a TGFβ type I receptor inhibitor. The invention also relates to a culture method using the primary cell culture medium and its application in the efficacy evaluating and screening of drugs. In the culture method, the primary cell culture medium is used to culture primary cells in a culture vessel coated with an extracellular matrix gel, to make the primary cells expend rapidly. A cell model obtained using the primary cell culture medium and the primary cell culture method can be used for the efficacy evaluating and screening of drugs.