The behavior of Na in SiO₂ film during SIMS depth profiling was characterized by varying the sample temperature from 154 K to 303 K under the condition of self-compensation of charges. The depth distributions of the defects in the films were analyzed also using ESR and FT-IR, and the influence of the defects on Na behavior during SIMS analysis is discussed. At lower temperatures, the SIMS profiles almost fit that of a simulated Na distribution and it is considered that Na distributions are hardly affected by the defects in the film. However, with increasing temperature, the migration of Na toward the defects occurs and the resultant Na distributions are affected by the defects in the film. Thus, it was clarified that Na migration is induced by the defects in the film during SIMS analysis, even in the absence of the electric field caused by charging.