ABSTRACT  A laboratory experiment was conducted using some essential oils, i.e., Eucalyptus globulus, Eugenia caryophyllata, Cinnamomum cassia and Zingiber officinale to study their effects at different concentrations (1, 2, 3, 4% v/v) on the radial growth and spore germinations of, Ulocladium chartarum, Aspargillus niger , Fusarium semitectum and Geotrichum candidum , which were Isolated and identified of postharvest rots pepper fruits obtained from local markets using potato dextrose agar. The obtained results generally indicated that the tested essential oils significantly inhibit growth of the tested fungi. Eugenia caryophyllata oil was the most effective one, followed by Eucalyptus globulus of all tested concentrations, flowed by Cinnamomum cassia and Zingiber officinale oils at high concentrations. Moreover, some of the tested fungi were affected by all used essential oils, while Aspargillus niger was the most resistant fungi. Conclusively; it could be concluded that the tested essential oils were effectively inhibited the growth of the tested fungi that cause postharvest fruit rot diseases of sweet pepper at different concentrations tested (1, 2, 3, 4%).