Civil law is a legal system originating in mainland Europe and adopted in much of the world. The civil law system is intellectualized within the framework of Roman law, and with core principles codified into a referable system, which serves as the primary source of law.

The civil law system is often contrasted with the common law system, which originated in medieval England, whose intellectual framework historically came from uncodified judge-made case law, and gives precedential authority to prior court decisions

Historically, a civil law is the group of legal ideas and systems ultimately derived from the Corpus Juris Civilis, but heavily overlain by Napoleonic, Germanic, canonical, feudal, and local practices, as well as doctrinal strains such as natural law, codification, and legal positivism.

Conceptually, civil law proceeds from abstractions, formulates general principles, and distinguishes substantive rules from procedural rules. It holds case law secondary and subordinate to statutory law. Civil law is often paired with the inquisitorial system, but the terms are not synonymous.