The environment, as the basis of human life and future generations, has found a fundamental place in legal systems. Environmental damage is distinguished from other types of damage due to its characteristics such as collectiveness, irreparability, and impact on intergenerational interests, and the civil liability of the state in this area is considered an important issue in public law and the environment. In Iranian law, although Article 11 of the Civil Liability Law considers the state to be irresponsible in some cases, the evolution of legal ideas and Article 50 of the Constitution have provided the basis for accepting the state's liability for environmental damage. This liability can be based on fault or on the theory of risk without the need to prove fault. The main challenges in this area include proving the causal relationship, determining the competent authority to handle and calculate environmental damage. However, the importance of the state's civil liability is not limited to compensation for damage, but also plays an important role in ensuring the rule of law, achieving environmental justice, and government accountability. The result is that the government's acceptance of civil responsibility in the field of the environment is an undeniable necessity for sustainable development, protecting the rights of future generations, and maintaining ecological balance.