The role of three strains of cyanobacterial (blue-green algal), i.e., Nostoc muscorum, Spirulina platensis and Anabaena flos-aquae, was evaluated as bioagents on controlling the infection of faba bean by Rhizoctonia solani and Fusarium oxysporum. The activity of indole acetic acid (IAA), protease enzyme and total phenols showed an increase in the filtrates of Nostoc muscorum and Spirulina platensis than the filtrate of Anabaena flos-aqua. Culture filtrate of the three cyanobacteria species belonging to three genera caused significant reduction to the mycelial growth of R. solani and F. oxysporum. Treating faba bean seeds with any of algal culture filtrates before sowing in artificially infested soil with any of R. solani and F oxysporum (pot experiments) or in naturally infested soil (field experiments) resulted in significant reduction in both damping-off and dead plants (resulted from infection by root-rot and wilt diseases) compared with untreated seeds. Also, both N. muscorum and S. platensis were more efficient in reducing the infection by damping-off, root-rot and wilt at the high concentration (100%) than A. flos-aquae. On the other hand, treating faba bean seeds with any of the tested cyanobacteria filtrates significantly increased seed yield/plot compared with untreated seeds (control).