The Fall armyworm (FAW), Spodoptera frugiperda J.E Smith is an invasive pest that is now an important pest of maize crops in Indonesia and Bali in particular. This study aims to 1) determine the invasion process, 2) population development, and 3) the level of FAW pest attack on sweet corn and glutinous corn varieties in the Gianyar Regency, Bali. This study used a pair of plot design between plant varieties. A sampling of plants was carried out systematically randomly with a "U" shape. Furthermore, the sample plants were observed at intervals of one week. The results showed that the FAW invasion process had started since the plants were 1 week after planting (wap). Female moths prefer glutinous corn more strongly than sweet corn for the egg-laying process. The highest larval density was found at the age of 4 (wap) plants, respectively 30.6 larvae in glutinous corn and 26.0 larvae in sweet corn. The population development of FAW showed the same pattern in the two varieties of maize, namely the peak spawning occurred at the age of 2 (wap), while the peak population of larvae instar-1, -2, -3, -4, -5, and instar-6 respectively occurred at 2, 3, 4, 5, 6, and 7 (wap) respectively. The attack intensity of FAW showed the same tendency as the population density, which was heavier in glutinous corn, reaching 34.74% compared to sweet corn, which was 33.72%.