Leander High School is a secondary school in Leander, Texas, United States, and is part of the Leander Independent School District. It was established in 1983 and was the only high school in district, until the establishment of Cedar Park High School in 1998.^{[citation needed]}

The school has a freshman enrollment of 600 students and is accredited by the Texas Education Agency. Historically the school served a mainly rural population, but starting in the early 1990s the area experienced growth due to expansion of high tech industries in the nearby Austin area. In 1999, the school became an International Baccalaureate school.

As of 2017, the school principal is Chris Simpson.

The school's mascots are Leo the Lion and Leah the Lioness. The school colors are blue, white, and red.

The demographic breakdown of the 2,265 students enrolled for the 2025-2026 school year was:

Since the early 1930s, Leander has had a presence in Texas high school football. Since 1942, it has had 17 playoff appearances.

The 1942 season was the first time that Leander made an appearance in the playoffs after being named district champions. They were eliminated after losing to Marble Falls 0-26.

In 1955, Leander went 8-1-1 in the regular season, falling only to Thrall High School. They entered bi-district, but fell to Troy High School 0-12.