An experiment was conducted in the Agriculture Field Laboratory, Noakhali Science and Technology University (NSTU) to evaluate the effects of age of seedlings on the yield and growth performance of transplanted Aus (T. Aus) rice variety from April 2019 to July 2019. The experiment was carried out assigning four age of seedlings (T1 = 22-day old, T2 = 24-day old, T3 = 27-day old, T4 = 30-day old) and two rice varieties (V1 = BRRI dhan83, V2 = BRRI dhan65). The experiment was laid out in a Randomized Complete Block Design with three replications. In case of variety, the highest plant height (102.108 cm), the highest grain yield (2.643 t/ha), and the highest harvest index (32.317%) were obtained in BRRI dhan83 where the lowest plant height (87.804 cm), the lowest grain yield (2.431 t/ha) and the lowest harvest index (32.068%) were obtained in BRRRI dhan65. The age of seedlings had significantly affected total tillers/hill, effective tillers/hill, panicle length in T. Aus rice variety. The highest plant height (98.16 cm), straw yield (6.122 t/ha), the maximum number of effective tillers/hill (15.347) were obtained in 24 days old seedlings. The highest grain yield (2.634 t/ha) was obtained from 27 days old seedlings, and the highest harvest index (33.88%) was obtained from 22 days old seedlings. The lowest grain yield (2.429) was obtained from 24 days old seedlings, and the lowest panicle length (13.753 cm), harvest index (30.467%), and the minimum number of effective tillers/hill (13.753) were obtained from 30 days old seedlings. The lowest straw yield (5.075 t/ha) and plant height (93.16 cm) were obtained from 22 days old seedlings. In case of interaction, the highest plant height (104.667 cm) and the harvest index (34.86%) were observed in BRRI dhan83 at 27 days old seedlings. The highest straw yield (5.805 t/ha) was observed in BRRI dhan65 at 30 days old seedlings. The maximum number of effective tillers/hill (18.519) was observed in BRRI dhan83 at 24 days old seedlings. The highest grain yield (2.94 t/ha) was observed in BRRI dhan83 at 22 days old seedlings. The lowest plant height (80.67 cm) was observed in BRRI dhan65 at 27 days old seedlings. The minimum number of total tillers/hill (17.01) was observed in BRRI dhan83 at 22 days old seedlings; lowest panicle length (20.78 cm), the minimum number of grains/panicle (68.07) were observed in BRRI dhan65 at 24 days old seedlings; 1000 grains weight (22.76 g), the lowest grain yield (2.18 t/ha) were observed in BRRI dhan83 at 24 days old seedlings; the lowest straw yield (4.54 t/ha) was observed in BRRI dhan65 at 22 days seedlings old and lowest harvest index (29.09%) were observed in BRRI dhan65 at 30 days old seedlings. Based on the above results, it may be concluded that almost all of the yield and yield contributing characters of T. Aus rice performed best under the interaction between age of seedlings 22 days old seedlings and the variety BRRI dhan85.