Abstract: Thymallus arcticus grubei is only distributed in the Irtysh River basin in northern Xinjiang Uygur Autonomous Region in China. In recent years, due to overfishing and construction of water conservancy projects, its resources have declined sharply. It was listed as a second-level protected fish in Xinjiang Uygur Autonomous Region in 2004. This research carried out systematic observations on the embryonic development of artificially propagated Thymallus arcticus grubei, and recorded and analyzed the morphological characteristics of their embryos and larvae at various stages of development, aiming to provide necessary basic data for the breeding of Thymallus arcticus grubei and resource protection. The results showed that the fertilized eggs of Thymallus arcticus grubei were spherical, golden yellow, sinking eggs, unabsorbed eggs diameter (2.46±0.14) mm, water-absorbed eggs diameter (3.14±0.18) mm, and there were multiple oil droplets in the yolk. The number and spatial distribution of oil droplets changed regularly during embryonic development. Under the conditions of incubation water temperature (11.06±0.72)℃ and dissolved oxygen of 8.3—9.8 mg/L, it takes 301h to complete the entire embryonic development process, and the required accumulated temperature is 3384.84h·℃. There are 7 stages, zygote, cleavage, blastula, gastrula, neurula, organ formation and hatching, totaling 26 stages. The differentiation of caudal and pectoral fins and eye pigmentation of Thymallus arcticus grubei larvae have been completed in the late embryonic development of the fertilized egg, and the dorsal fin, pelvic fin, anal fin, adipose fin, etc. differentiated in the post-embryonic development process. The average length of the newly hatched larvae is (9.33±0.35) mm. The yolk sac and oil droplets are completely consumed at the age of 18 days. The growth characteristics of its early developmental stage (0—16 days old) conform to the formula: y=0.0005x⁴–0.0201x³+0.2264x²–0.3773x+9.6102 (R²=0.9968). This study preliminarily clarified the timing characteristics of the embryonic development and larval development of Thymallus arcticus grubei, and provided a theoretical basis for the future large-scale breeding of seedlings.