It has long been known that lactoferrin prevents human beings from infection of virus. To prove this activity of lactoferrin, we evaluated the activities of different lactoferrins to an isolate human rotavirus K-21. Bovine lactoferrin inhibited infection of K-21 to MA-104 cell at the concentration of $25.9;{mu}M$ whereas bovine hydrolysed lactoferrin prevented rotavirus infection at $103.8;{mu}M$. However human lactoferrin prevented infection of K-21 at the concentration of $217.5;{mu}M$. These data suggested that lactoferrin activity may be unaffected by the intestinal digestive enzymes and bovine lactoferrin is more active than human lactoferrin with respect to prevention of rotavirus infection.