In the Turkish legal system, civil liability based on fault is the basis of civil liability resulting from a harmful act. According to Article 49 of the Turkish Law of Obligations, in civil liability resulting from a harmful act, liability is essentially a kind of fault, which is the most important element of liability. In addition to this type of liability, no-fault liability is provided in exceptional and special cases. But in the Afghan legal system, the issue is quite different. According to Article 758 of the Civil Code of Afghanistan, civil liability resulting from a harmful act is in principle of the type of liability without fault. However, in addition to the liability without fault, which is derived from Islamic jurisprudence and has been accepted as a principle, the legal institution in its article 760 also accepts the cause or responsibility as an exception. The difference between the views of the two legal systems on fault and civil liability based on fault indicates the efforts of each of them to fill the gap in this type of civil liability system and try to reduce irreparable losses. What is certain is that the difference in the meaning and concept of fault in both legal systems affects the type of acceptance of this institution of civil liability, its legal effects and consequences, and the neighbors of damages. This difference in view of the fault and fault-based liability reflects the need for comparative research, which is addressed in this paper.