The present invention provides a naphthoquinone compound that exhibits antibacterial and antiviral activities against various fungi and bacteria. It is a compound represented by formula (I) [where R 1 is hydrogen or OR, R is hydrogen, C 1-6 alkyl or C 1-6 alkyl-CO] or a compound that is pharmaceutically acceptable salt.本發明提供一種顯示出對各種真菌及細菌之抗菌活性及抗病毒活性之萘醌化合物。其係一種式(I)[式中,R1為氫或OR,R為氫、C1-6烷基或C1-6烷基-CO]所示之化合物或其製藥學上所容許之鹽。