The invention discloses an intelligent monitoring system for an assembling process as well as an assembling system and a monitoring method thereof. The intelligent monitoring system for the assemblingprocess comprises a pick-up device, an image recognition module, a data storage module, a monitoring module and a warning module. An operation tool prepared from a zero refractive index material in the assembling system is used for carrying out assembling operation; the pick-up device is used for carrying out image sampling on an assembling technique; the image recognition module is used for carrying out error recognition and monitoring statistics on the technique, judging result, finding errors and transmitting an error correcting prompt to the warming module. The system and method thereof disclosed by the invention have the advantages that the whole assembling process can be recorded, recognized, corrected and digitalized, data feedback loop can be provided for an assembly production line and the like.