With the development of electronic contracts, the role of Internet Service Providers (ISPs) in providing the infrastructure for the formation of contracts, exchange of data messages, authentication, data retention, and execution of electronic obligations has gained increasing importance. The dependency of these contracts on technical and communication infrastructure means that any disruption, security breach, delay in data transmission, deletion or distortion of information, and failure in internet services can lead to damages to the parties of the contract or third parties. However, in Iranian law, there are no comprehensive and independent regulations governing the liability of all types of Internet Service Providers, and the analysis of this liability is inevitably based on general principles of contract law, civil liability, the Electronic Commerce Law, and Islamic jurisprudential principles of Dhaman. Using a descriptive-analytical method, this article aims to examine the foundations and conditions for establishing the liability of ISPs during the process of concluding and executing electronic contracts. The research findings indicate that the liability of these entities can be contractual or tortious, depending on the circumstances; meaning that in the presence of a contractual relationship, the breach of express or implied obligations forms the basis of liability, and in the absence of such a relationship, the rules of civil liability and Dhaman-e Qahri are applicable. Therefore, the mere occurrence of damage in the electronic environment is not sufficient to hold ISPs liable; rather, the attribution of the damage to their conduct must be proven. Finally, the article concludes that the liability of these entities in Iranian law is fundamentally based on fault, unless the law, the contract, or the nature of the activity dictates a stricter standard of liability.