In order to overcome the shortage of volatileness, easily oxidized and pungent odor of arlic oil, the garlic oil microcapsules were prepared by spray-drying process with modified starch as the wall material. Ordinary waxy corn starch was preliminary modified by low pressure plasma technology. The preparation technique on garlic oil microencapsulation was optimized. The effects on the storage stability and bacteriostatic of saccharomyces cerevisiae were compared between before and after the reform of microcapsules. The results showed that film-forming performance of waxy corn starch had been significantly changed after being treated by the low pressure plasma. The optimum process of starch modified conditions of garlic oil microencapsulation was as follows: the concentration of wall material was 15%, the concentration of core material was 20%, the inlet temperature was 180 ℃, the feed temperature was 45 ℃, the embedding rate was 92.3%. The storage stability and bacteriostatic effect of the modified starch microcapsule were better than that of ordinary waxy corn starch microcapsule.