Katharine Fredrica Lenroot (March 8, 1891 – February 10, 1982), an American feminist and child welfare advocate, was the third Chief of the United States Children's Bureau.

She attended Superior State Normal School finishing in 1909.

Instead of going straight into college Lenroot joined her father in Washington D.C.

[1][2][3][4] Lenroot completed her bachelor's degree in 1912 and began work in the civil service as deputy of the Industrial Commission of Wisconsin in 1913.

Lenroot was president of the Pan-American Child Congress, in 1942, and represented the US on the board of UNICEF from 1947 to 1951.