We investigated the usefulness of the promoter of a gene for tobacco elongation factor 1α protein (EF1 α) for transgene expression in the chrysanthemum (Chrysanthemum morifolium Ramat.). The EF1 α promoter was fused to the β-glucuronidase gene (gus) and introduced into the chrysanthemum. We obtained 238 putative transformants and GUS assay of the leaves of the in vitro plants revealed that 29.0% (69/238) of the putative plants were GUS-positive. The plants in the greenhouse that were 20 months after regeneration still showed a GUS activity in their leaves and petals. The tobacco EF1 α promoter expressed the transgene more efficiently than the 35S promoter of Cauliflower mosaic virus and could be used for transgene expression in chrysanthemum.