Due to lack of standardized description for the current Maintenance Disassembly Process, leading to semantic ambiguity problem when different modeling interacts, this paper discussed about Modeling of Maintenance Disassembly Process Based on Semantic Ontology. It classified the concept of disassembly with two types of semantic ontology primitives including Concept and Instance. Described hierarchical relations between concepts by Relation primitive.Separately described the nature and logical constraints in disassembly process by Attribute and Function Primitive. And then abstracted this description in the form of quintet to present the Maintenance Disassembly Process ontology model, which makes the disassembly process in the same semantic environment in which the knowledge of disassembly could be reused and shared. Finally it presented an instance of disassembly process of Transceiver-VHF (1RC1) to verify the validity of the model, solving the problem of semantic ambiguity.