Nowadays, the increase in using the contracts in which one party has a stronger position against the weaker party provides the stronger party a possibility to insert some unfair terms in contract. In recent years, some countries have tried to enact some legislation to protect the weaker party against such terms. This Article examines comparatively regulations on unfair contract terms in EU in order to consider its historical development, what an unfair contract term is and why the weaker party should be protected against such terms. General contract rules and some special protective Acts that have been adopted in recent years in Iranian law arises the question of how the protection of weaker party considers, especially consumers, against u...