The invention discloses a data storage system and method of a portable master station. A data execution CPU transmits data to a data writing register through a data writing bus, the data writing register transmits the data to a data sharing bus, a data reading register obtains the data from the data sharing bus and transmits the data to the task execution CPU through a data reading bus, the task execution CPU transmits an instruction to an instruction writing register through an instruction writing bus, the instruction writing register transmits the instruction to an instruction sharing bus, and the instruction reading register obtains the instruction from the instruction sharing bus and transmits the instruction to the task execution CPU through the instruction reading bus. The reading and writing processes of the data instruction both have reverse detection paths, the data reading bus, the data writing bus, the instruction reading bus and the instruction writing bus are separated, the relative stability of data storage of the portable master station system is achieved, and the system and method have the advantages of being high in efficiency, good in performance and low in cost.