Tomato mosaic virus (ToMV) was isolated from naturally infected bell pepper plants in different areas at Menoufia Governorate, Egypt. The isolates were characterized by its reaction in indicator host (Nicotiana glutinosa L.) and systemic host (Capsicum annum L cv. Balady), serological reaction (DAS-ELISA, TIBA and DIBA) and electron microscope (EM). In addition to estimate the effect of four plants leaf extracts, guava (Psidium guajava), solanum (Solanum nigrum), spinach (Spinacea oleracea ) and thyme ( Thymus vulgaris ) with three concentrations ( 2.5-5-10 % of stock ethanolic crude extract) on ToMV infection. Results showed that all plant extracts were efficient in reducing the local lesion formation by the virus on Nicotiana glutinosa. The extract of Solanum nigrum gave the highest inhibition percentage at all concentrations. Percentage of infection and disease severity (%) of bell pepper plants (Capsicum annum L cv. Balady) were measured in response to systemic induced resistance (SIR) to ToMV infection. Treating of all inducers on infected bean leaves were effective in reducing infection percentage and disease severity compared to infected control. Extract of Solanum nigrum L. was the greatest efficient against ToMV as a factor of resistance induction. It reduced percentage of infection by (20 %) compared to un-treated control (92%) and reduced disease severity by (15 %) compared to un-treated control (89.34%).