To address the problems of lack of germplasm resources, unclear adaptability and lack of excellent parents of aromatic japonica rice in cold region of Inner Mongolia, this study analyzed 127 rice germplasms in terms of their growth period, agronomic traits and fragrance gene, aiming to provide parental materials and theoretical references for fragrant rice breeding in Inner Mongolia. Field adaptability identification was carried out in Hinggan League for 2 years using single-plant transplanting, and agronomic and economic traits were systematically investigated throughout the entire growth period. The results showed that all the tested germplasms could mature normally, with early-maturing, medium-maturing, medium-late-maturing and late-maturing types accounting for 2.36%, 33.86%, 41.73% and 22.05% respectively, and medium-late-maturing types (146-155 days from sowing to maturity) was the dominant type. The traits were characterized by yellowish glume tips and culms, medium-sized panicles and tillers, small flag leaf angles, awnless and strong lodging resistance; medium-statured plants (56.69%) were the majority, and medium-sized panicles (69.29%) were the most common; 69.29% of the germplasms had a grain-filling rate of ≥90%, and 95.28% had medium-width second upper leaves. A total of 103 materials carried the badh2-E7 fragrance gene. This study screened out 23 fragrant rice germplasms, with their full heading period concentrated from July 21^st to 26^th, and the average stem length was 83.64 ± 10.37 cm, which can provide excellent parental resources for fragrant rice breeding in Inner Mongolia. The study clarified the phenotypic rules of fragrant rice germplasm in the northern cold region, and provided theoretical basis for the breeding of high-quality fragrant rice in the Inner Mongolia rice region. Subsequently, hybrid mating group and yield, stress resistance and taste can be improved simultaneously.