The aim of the study is to know the effect of contaminated microbes on human health and what their harms are, the importance of the extent of the effect of foods not prepared in a safe and correct manner and the presence of microbial load in these foods, what are the causes or risks of people being exposed of food poisoning to a large extent as a result of these foods, what are the health steps or procedures to avoid them. Food contamination with microbes. What is the role of hygiene in avoiding the dangers of food with microbes. questionnaire was created through the Google Drive application, where this questionnaire was distributed to social networking groups WhatsApp, where 700 answers were obtained from those (health practitioners of the city of Mecca), out of a total of 650 questionnaires. Keywords: effect, foods contaminated, microbes, human health