The question of the stude is: what is Imam Khomeini's opinion about Velayat-e-Faqih? How does he base his view on reasonable foundations? What role does it play in proving its intellectual foundations and political jurisprudential opinions about Velayat-e-Faqih? For this purpose, his argumentative and principled jurisprudential texts, opinions and rules have been studied based on the method of content analysis. As described in the study, he accepted the reason as one independent agent for the principles of inference throughout the book and tradition. The use of reason in deriving Shari'a rules in the works of Imam Khomeini reaches its ultimate degree where he establishes an institution as an expediency. Imam Khomeini first expressed his views on Velayat-e-Faqih in the book "Kashf-e Asrar"; in that book he proved the necessity of law and government in human society with a rational proof.