[en] The data acquisition system for large amount data have been developed with the mass storage system of JAERI to reduce loads for the data processing, especially for the management of magnetic tapes, and to simplify procedures of the data processing. Data of the Cylindrical Core Test Facility (CCTF) test were used as a sample. All data of the CCTF test was store in the mass storage system of JAERI to minimize the load for the managements of magnetic tapes. Program for data dump, plot and analysis of the CCTF test, AREAD1, has been developed to simplify procedure of the data processing. TSS comand procedure, PLOT, has been also developed to reduce the turnaround time for data plot. In the new data acquisition system, magnetic tapes were used only once as inputs to store data in the mass storage system and the load for managements of magnetic tapes was reduced extremely. The turnaround time of the data processing was also reduced by the development of the new data acquisition system. It took only a few minutes to get a plot of data by the new data acquisition system, while it took a few hours by the old data acquisition system with magnetic tapes. (author)