A potent germination inhibitor was found in the hexane soluble fraction of the methanolic extract of Eucalyptus pulverulenta. This inhibitor was identified as grandinol (1) which had been isolated from E. grandis. On the cress germination test, 1 showed I50 at 10 ppm. The other eight compounds in the fraction containing 1 on silica gel chromatography were also identified. Compounds (2) and (3) are regarded as phloroglucinol metabolites characteristic of the Eucalyptus species. The known compound (4) may be a good taxonomical marker for E. pulverulenta, and (5) ~(9) are possibly common metabolites of Eucalyptus.