Abstract: Fifty-three Blastocystis hominis isolates were separated from the fecal specimens of carriers in college students from Guangxi and cultivated in vitro， and the genetic DNA was extracted. All the isolates were genotyped by PCR using seven pairs of known sequence-tagged site（STS） primers. The results showed there were five subtypes in the 53 isolates. Subtype 3 was the most popular one （32.1%, 17/53）, followed by subtype 7 （9.4%, 5/53）. Subtypes 1 （7.6%, 4/53）， 4 （7.6%, 4/53）， and 6 （1.9%, 1/53） were detected， while subtypes 2 and 5 were not detected. The genotypes of the other 22 isolates were unknown which were negative to all the STS primers.

Key words: Blastocystis hominis, Genotype, College student, Infection