An object of the present invention is to provide a method for increasing the expression of foreign genes, in particular, using a promoter, an enhancer, and the like, and an expression cassette containing a promoter, an enhancer, and the like, by which gene expression can be increased. The purpose is achieved with the use of the gene expression cassette comprising a DNA construct containing a gene to be expressed and a poly A addition sequence that are located downstream of a 1st promoter, and further comprising an enhancer or a 2nd promoter ligated downstream of the DNA construct.