The median age in Middle River Township, Minnesota is 33.3, as per 2021 ACS 5-Year Estimates. Of the total population, 26.92% were under the age of 15, 15.38% aged 15 to 29, 42.31% aged 30 to 64, 15.38% aged 65 to 84, and 0.00% were 85 years of age and older.