Disassembly is essential to dismantle a product for remanufacturing during maintenance or at the end of service life. The National Institute of Standards and Technology (NIST) has developed an information model for describing disassembly processes. A disassembly process includes many subprocesses, such as separation, cleaning, repair, replacement, and inspection. This paper describes a disassembly process information model with the following key components: workpiece, material content, equipment, and workflow. The workflow aspect supports the modeling of operations, operation sequences, branching an operation into multiple ones, and joining multiple operations into one. The model provides a foundation for computer-aided disassembly software systems development.