Fungicidal effect of leaf aqueous extracts of Azadirachta indica, Tithonia diversifolia and Chromolaena odorata were determined on rot causing fungi. In the study, the phytopathogenic fungi isolated from the infected tomato fruit parts and identified based on morphological and cultural characters were: Aspergillus Niger Van Tiegh, Fusarium oxysporum Schlecht, Geotrichum candidium Link and Rhizopus stolonifer Ehrenb. ex. Fr. as confirmed by pathogenicity tests. Leaf aqueous extracts of different concentrations (20, 40, 80, 60 and 100 % w/v) of A. indica, T. diversifolia and C. odorata were added to growth media prior to inoculation. All aqueous extracts of the tested plants significantly (p < 0.05) reduced mycelial growth of the fungal pathogens and this effect gradually increased with increasing concentration. Fungicidal activity was strongly exhibited by A. indica extract at 100% w/v against all the pathogenic fungi. In the case of T. diversifolia extracts inhibitiory effects at 20, 40, 60, 80 and 100% w/v were greater than those of C. odorata on A. Niger , F. oxysporum and G. candidium while for R. stolonifer inhibition, C. odorata produced the highest in the all five concentrations than T. diversifolia extracts. It could be emphatically concluded that the tested plant extracts can effectively control rot causing fungi disease of tomato. This makes them potential biocide in diseases management in that they are cheap and environmentally safe as they showed fungicidal and fungitoxic ability.