The school, originally established in 1889 along with Washington's statehood, did not move to its current location until 1963.

By the early 1900s, the student body population had reached about 260, and the first real high school building was erected in 1904.

By 1917, the school was so overpopulated that shacks furnished with church pews were being utilized as classrooms.

Walla Walla High School is a comprehensive public high school (operating on a semester schedule) Priding itself on serving the needs of a diverse student body through programs including Advanced Placement, College in the High School, Career and Technical Education, Running Start, University Enrichment Programs, and AVID, Wa-Hi offers a complete array of positive learning opportunities to its students.

Recent accolades awarded to the establishment include: Washington Achievement Award 2010 - Closing the Achievement Gap, Washington Achievement Award 2011 & 2012 - Extended Graduation Rate, US News & World Report 2013 - Silver Medal, Washington Achievement Award 2013 - High Progress, Washington Achievement Award 2014 - High Progress, US News & World Report 2014 - Silver Medal, US News & World Report 2015 - Silver Medal, 8th Annual AP District Honor Roll –2017, US News & World Report 2019 - Silver Medal, US News & World Report 2023-2024 - Best High School Rankin.