Under greenhouse condition, there was a positive rela¬tionship between inoculum density and disease incidence with Sclerotinla sclerotiorum fungus. Biological treatments were more effective than treatment with Vitavax/Captan 75 to control Sclerotinia rot disease on beans cv. Giza 3. There was no significant difference between bio- and chemical treatments on bean cv. contender Spore suspen¬sions of different antagonists were effective in controlling the disease on lettuce than culture filtrates. Fungicide 'Benlate 50" was more effective than culture filtrates of antagonists but less effective than spore suspension of these antagonists. Adding antagonists as granules was more effective than adding them as spore suspension. There was a negative rela¬tionship between the rate of application of antagonists and disease incidence in beans. When lettuce was used as host plant, spore suspension at a rate of 60 ml/pot was more effective than adding antagonists as granules Residual effect of the biological treatment of antago¬nists especially when added as granules was more durable than the chemical treatment with Vitavax/Captan 75 Under field conditions biological treatment with Trichoderma harzianum and Chaetomlum globosum controlled disease incidence giving significant increase in yield of beans and lettuce comparing with the chemical treatments