Background: Food is a vital substance that helps in the nutritional support and development of the human system and so the issue of food is important for every human being. Food is usually of plant and animal origin and contains nutrients needed by the body and could also be a source of ill health to humans if it is contaminated by microbes through poor hygienic practices. Objectives: The specific objectives are to identify cooked food storage hygiene practices among food vendors in public secondary schools in Oshimili south L.G.A and to determine personal hygiene practices of the food vendors in public secondary schools in Oshimili south L.G.A. Methods: Quasi-experimental design was used for the study. This involves two-phase work using Pre-test and Post-test. The representative sample size of 54 food vendors used for the study was gotten from the school food vending registers of the various schools. Data were entered using Microsoft Excel Windows 7 and exported to IBM SPSS version 15.0 software for analysis. Results: From the finding, more of the vendors (62% and 30%) transport their foods/snacks in closed containers and warmers after the health education intervention. Also, more vendors (Always 46%) started keeping their fingernails clean after the intervention. Similarly, more vendors practiced hand washing after the health education intervention. 41% of the food vendor never practiced hand wash but this was reduced to 26% in the Post-test. Likewise, the number of vendors that never covered food against dust and flies during sales reduced from 10% in Pre-test to 6% in Post-test study. The finding also showed that the vendors clean and sweep their vending environment before and after-sales. From the hypothesis testing, it was established that the health education intervention had a significant influence on the food vendors’ hygiene practices (p<0.05). Conclusion: The food vendors’ hygiene practices were still poor despite some notable improvement after the health education intervention. The school management seems not to be concerned about the hygienic practice of the food vendors and nobody monitors their activities during sales rather they are more concerned about collecting dues from the food vendors monthly. It is therefore recommended that School management should ensure that the food vendors are regularly trained on proper food handling and teachers are also delegated to monitor the food vendors during sales at break time. The government should post health officers to schools in order to monitor food vendors’ hygiene practices on a regular basis.