Valerenic acid, isolated from VALERIANA OFFICINALIS L. s.l. affected the rotarod and traction performance of mice in a similar manner to that of pentobarbital which was used together with chlorpromazine and diazcpam as reference substance in both tests. A decrease of locomotility of mice was also noticed after administration of valerenic acid, in particular when this compound was administered to the same group of mice a week later than the vehicle. In addition valerenic acid was found to prolong the pentobarbital induced sleeping time. It can be concluded, that valerenic acid has aspecific central nervous depressent properties. This factor should be taken into account when considering the sedative action of Valerian preparations.