Field studies were performed in Ashmon district, Menofia Governorate, to evaluate the efficacy of four chemical fungicides and one bioagent against wheat diseases in wheat (C.V. Gemiza 9) fields during the two successive seasons (2013-2014 and 2014-2015) incompasion with untreated control. The chemical fungicides were (Vitavax 200 75% WP (carboxin +thiram), Sumi eight 2% WP (diniconazole), Rovral 50% WP(iprodione) and Rizolex – T 50% WP (tolclofos- methyl +thiram ), whereas the bioagent was Plant- guard (Trichoderma harzianum) 30 million spores cm^-3. All the tested compounds were used as seed treatments at the rate of 1, 2 and 3 g kg^-1 of seeds. Generally, all the tested compounds increased the number of plants m^-2 compared with untreated control. Diniconazole and iprodione fungicides were the most effective fungicides, Plant- guard was the least effective while the other compounds showed intermediate effects. Diniconazole and iprodione also significantly reduced the number of rotted roots at 21 days after sowing (DAS), and increased the number of tillers plants^-1   compared with untreated control. The fungicides diniconazole and tolclofos- methyl +thiram reduced the number of white head m^-2, also diniconazole and carboxin +thiram reduced the number of scabby heads m^-2. Generally, increasing the rate of application significantly increased the efficacy of the tested compounds, and the chemical treatments were more effective than the bioagent in all cases. Results also showed that seed treatments with these compounds particularly diniconazole, tolclofos- methyl +thiram and iprodione increased the grain and straw yield.