This study aimed to investigate virus occurrence in weed species in the main pepper-growing areas in Southwest Nigeria. The weed samples collected from pepper farms were identified and subjected to Antigen-Coated Plate Enzyme-Linked Immunosorbent Assay using antibodies specific eight different viruses. Results showed that the Weed species collected contain 17 families, 33 genera and 36 plant species of which 83.33% of the plant species tested positive to one or more plant viruses. The results indicate that potato virus Y (PVY) and potato virus X (PVX) infected more weed species (24). Also, Ageratum conyzoides serve as host to 8 viruses while Alchornea cordata, Corchorus olitoris and Talinum triangulare serve as host to 7 viruses respectively. These results provide information on weeds as virus reservoirs and contribute to the knowledge of epidemiology of these diseases, enabling a proper weed management aiming at reducing the secondary spreading control of viruses. [ABSTRACT FROM AUTHOR]