An object is to provide an SWCNT slurry for bioimaging with reduced toxicity that causes no aggregation of semiconductor SWCNTs, no accumulation in a specific site when administered to a living organism, and no clogging in blood vessels such as those in the lungs. In order to achieve the above-described object, a semiconductor single-walled carbon nanotube (SWCNT) slurry for bioimaging according to the present invention includes: semiconductor SWCNTs having an average particle size of less than 10 nm; and a dispersant composed of an amphiphilic substance that coats the surfaces of the SWCNTs.