The invention relates to a three-dimensional large-space multi-channel pen-based interaction system, and relates to a three-dimensional large-space multi-channel pen-based interaction system. The system comprises a main unit and an intelligent electronic pen. An ultrasonic signal, acceleration and gyroscope signal combination pen-based identification method is used for completing auxiliary positioning according to an acceleration and a gyroscope signal under a condition that pen-based identification of an electronic pen cannot be realized through an ultrasonic signal due to shading, and also realizes extraction of pen attitude information. The three-dimensional large-space multi-channel pen-based interaction system and method support pen-based interaction, gesture interaction and voice interaction operations in a three-dimensional space and on a two-dimensional plane, and have the advantages of high positioning precision, large interaction space, capability of supporting a three-dimensional book empty mode and the like.