The silicon-on-insulator (SOI) CMOS technology has a number of advantages over the standard bulk CMOS technology such as negligible latch-up probability, high speed and low power dissipation. The fully depleted SOI (FD-SOI) CMOS technology provided by OKI Electric Industry Co., Ltd. is realizing the full features of the advantages. Although the total dose response of SOI devices is more complex due to the presence of the buried oxide, high radiation tolerance is expected for a very thin silicon layer. We investigated the total dose effects on transistors fabricated using the OKI 0.15μm FD-SOI CMOS process. Assuming a radiation environment at the super LHC experiment, we have irradiated with 70 MeV protons three chips each to 6.4×1013, 5.8×1014, and 5.5×1015 neq/cm 2. In this paper we report the latest results in comparison with the data taken in a 2006 exposure test.