Established in 1865, it is owned and operated by the Wisconsin Evangelical Lutheran Synod (WELS).

The prep department received its own identity in 1974 as Northwestern Preparatory School (NPS).

[5] The mission of Luther Preparatory School is to prepare and encourage young men and women for the full-time ministry in the Wisconsin Evangelical Lutheran Synod.

Fall sports include football and soccer for boys, volleyball and tennis for girls, and cross country for both.

Spring sports are baseball, softball, track and field, boys' tennis, girls' soccer, and golf.