Abstract: The single-event upset (SEU) of SRAM with feature size of 0.15 μm was tested on the single-event effect (SEE) test facility of Beijing HI-13 tandem accelerator, and the results were compared with published test results. It is found that the SEU cross section of the high energy ion is slightly smaller than that of the low energy ion as the cross section is close to saturation cross section. Through calculating with Monte Carlo simulation tool Geant4, it is concluded that the high energy ion deposits more energy at far distance, so it is easier for high energy ion to make the adjacent nodes in same memory share charge and to lead SEU recovery. Then the SEU cross section becomes smaller. The SEE test result of low energy ion is relatively conservative.