One of the most important issues in the international scene in recent decades has been humanitarian law. The purpose of humanitarian law is to protect human beings in armed conflicts and limiting the use of certain warfare and methods during a war. In fact, humanitarian law deals with principles principles which limits inhuman behavior during a war. Imam Khomeini who was the chief commander of the eight year war, strictly adhered to these rules and regulations based on Islamic laws and regulations. In spite of violating such regulations by the Iraqi army, he never allowed infringement of those laws. In this contribution, by using analytical -descriptive method, I have tried to explain Imam Khomeini’s views on humanitarian law. At the end, the conclusion indicates that human behavior, denial of raid and ambush in armed conflicts, the distinction between military personnel and civilians, restrictions on the use of weapons, proportionality and necessity of military action, love and kindness to prisoners of war and protection of environment have been considered as the most important principles of humanitarian law in Imam Khomeini’s thoughts.