The importance of the research is due to the fact that it is trying to explain the status of al-Farabi's in Islamic thought and the extent of its influence on Greek philosophy, especially the thought of Plato. His philosophy was also of a reconciling nature between philosophy and religion and between what should be the political and religious life to achieve happiness and social justice in society. Al-Farabi's was influenced by Plato, so his behavior and way of life were clear Platonic, and it had a great impact on his ideas in morals and politics. Research limits: The research was divided into five sections, as we studied in the first topic the necessity of human meeting and the types of societies, and in the second topic we explained the nature of the virtuous city, and in the third topic we studied the non-virtuous city, and in the fourth topic we talked about the president of the virtuous city and showed the most important characteristics that He enjoys it, and in the fifth topic, we explained the powers of the ruler in the virtuous city, and then came the conclusion and a list of sources and references.