Provided in the present invention is the use of a mevalonic acid pathway inhibitor in the preparation of a drug for treating and/or preventing tumours, inducing immunogenic death of tumour cells, inducing immune responses and activating T cells or DC cells to directly promote host immunity. Also provided in the present invention is a pharmaceutical composition comprising the mevalonic acid pathway inhibitor and an antitumour drug (for example, an immune checkpoint inhibitor and any drug that can lead to new antigen production) and a combination of the mevalonic acid pathway inhibitor and an antitumour drug (for example, an immune checkpoint inhibitor and any drug that can lead to new antigen production) and/or the radiotherapy.
