The mutability and frequency of genetic reassortment characteristic of rotavirus and resultant antigenic changes make the rotavirus formidable challenges for control efforts such as the vaccine development. An alternative approach to overcome these difficulties in development of the rotavirus vaccine is to develop effective inhibitors of the virus infection. As an effort to achieve this, effects of glycyrrhetinic acid (GA), which is an active component of glycyrrhizin, on MA-14 cell infection were examined by employing the human rotavirus isolated from Korea, K-21. The data obtained showed that MA-104 cell infection of the K-21 rotavirus was greatly influenced by the presence of both $18{alpha}-Ga;and;18{eta}-GA$. Both types of GA have inhibited more than 60% of the rotaviral infection at the concentration of 7.68mM. This inhibition effect became much more evident at the higher concentrations of GA. However, the type of GA did not make much differences on the inhibition effect of the drug. Although GA has to be used in high concentrations to exhibit anti-viral activity and to be virostatic, a long history of safe and high dose usage of licoriece in clinical settings in the Far East makes the GA as an attractive inhibitor of the rotaviral infection.