Allelopathic effect of Eucalyptus microtheca F. Muell. was studied in laboratory experiments. The aqueous extracts from different dried plant parts, soaked for 48 hours, inhibited radicle growth, plumule growth and seed germination of Pennisetum glaucum cv Bari-Hairy. However, no serious inhibition of seed germination was occurred. The toxicity varied from part to part and was related to concentration and soaking duration Root exudates were highly toxic to the radicle growth followed by leaves, stem and whole plant material For the growth of plumule, leaves were found to be highly toxic followed by whole plant, roots and stem. Enhancing effect on the growth of radicle was not observed However, it was observed on the growth of plumule by roots and stem extracts only.