Within-wafer total ionizing dose (TID) response variability on buried oxide (BOX) layer of silicon-on-insulator (SOI) technology is investigated in this article. TID response variability is measured by the threshold voltage and OFF-state leakage of transistors evenly distributed on the wafer locations. Experimental results show the larger standard deviation of threshold voltage and OFF-state leakage distribution for irradiated devices than unirradiated devices, illustrating the within-wafer TID response variability. The hole traps variation in the BOX layer is responsible for the within-wafer TID response variability of SOI technology. Moreover, a data analysis method according to T-distribution is proposed to obtain the within-wafer TID response variability by the sampling testing results of limited wafer locations. Our data show that the T-distribution method is reasonable to assess the TID-induced variability of a process when only a few samples are available.