A comparative study of the morphological characters of seedlings was made for the different types of super rice varieties, both in the early and late crop. The results showed that, under the ecological conditions of double rice cropping system in the southern China, a significant difference of F-value at 1% level existed among plant height, leaf number of main stem, stem number each plant and basal width of leaf sheath in the tested varieties. According to the results, the ideal morphological characteristics of South-China double cropping super-rice at the seedling stage were determined. They are 35.0-37.5 cm in the early crop and 33.5-35.5 cm in the late crop for the ideal plant height, 2.0-3.0 in the early crop and 3.0-3.2 in the late crop for the tillers per plant, 5.8 leaves in the early crop and 4.9 leaves in the late crop on the main stem, 0.71 cm in the early crop and 0.51-0.54 cm in the late crop for the width of basal leaf sheath.