Measurements on stratospheric aerosols at Syowa Station (69¿00'S, 39¿35'E) in 1983, 1984 and 1985 are described. The year-to-year changes in aerosol content were influenced by volcanic eruption of Mt. El Chichon (spring 1982, Mexico) and variations of stratospheric temperature. The aerosol load in winter of 1983 was about five times larger than the load of 1985. The particle content of spring 1985 was larger than that of spring 1983 even though the effect of the volcanic eruption was more severe in 1983. This may be a result of the decrease in average stratospheric temperature in spring. If heterogeneous reactions including the particles are indeed important for Antarctic ozone depletion, the rate of ozone depletion from heterogeneous reactions in the Antarctic spring must have increased from 1983 to 1985.