This study aims to examine civil liability arising from damages caused by animals in UK’s and Iran’s law. To achieve this goal, a comparative research method has been employed, analyzing statutory laws, judicial precedents, and legal doctrines in both legal systems. The findings of the study reveal that in UK’s law, civil liability for damages caused by animals is based on two principles: fault and strict liability, with the Animals Act 1971 providing specific frameworks for dangerous and non-dangerous animals. In Iran’s law, Article 334 of the Civil Code and the Islamic Penal Code address the liability of animal owners or custodians based on the fault theory. The conclusion indicates that despite conceptual similarities between the two legal systems, UK’s law, with its longer history and more precise regulations, offers greater protection to victims. In contrast, Iran’s law demonstrates a clear need for reform and further development in this area.