Abstract Digital twin is a concept redefined with the emergence of Industry 4.0, reflecting the physical characteristics of a certain physical entity into its numerical/digital model in the cyber space. Machine Tool Digital Twin (MTDT) is the application of the digital twin concept on machine tools. MTDT enables thorough analysis of the physical behavior of the machine tool during its operation. This research presented a framework in which a high-level data model, i.e. Standard for the Exchange of Product data compliant for Numerical Control (STEP-NC) is utilized to deliver a rich structured information of the machining process. This data model is machine independent and an international standard. The combination of MTDT and STEP-NC enables establishment of a knowledgebase, which can be utilized for machining process optimization.