An object of the present invention is to provide a method for microbioiogically producing astaxanthin of high concentration at low cost while suppressing production of canthaxanthin. Specifically, the present invention relates to a method for producing carotenoids including astaxanthin comprising culturing a bacterium that concurrently produces astaxanthin and canthaxanthin in a medium containing biotin, wherein a ratio of concentration of produced canthaxanthin to concentration of produced astaxanthin in a culture product after the end of culture in the medium is lower than that in a culture product alter the end of culture in a biotin-free medium.