Townsend Harris High School (often shortened to Townsend Harris or simply Townsend, and often abbreviated as THHS) is a public high school for the humanities in the New York City borough of Queens. It is located on the campus of Queens College, a public college part of the City University of New York system. The school was named in honor of Townsend Harris, the 19th-century American merchant, politician, and diplomat who served as the first American Consul to Japan. The school's students and alumni often refer to themselves as "Harrisites".

Townsend Harris High School was founded in 1984 by alumni of Townsend Harris Hall Prep School, who desired to reopen their school that was closed in the 1940s. This process started in 1980.

The first principal was Malcolm Largmann, a former high school English teacher with a strong belief in a classical education who also handpicked the school's original faculty. Largmann served as principal of Townsend Harris from 1984 until his retirement in 2001. He would die in 2021. The new school began in a small building on Parsons Boulevard, originally intended as a temporary home until a permanent facility could be realized. In early 1995, the school moved into a new building located on the campus of Queens College.

In 2000, Eileen F. Lebow published a history of the original school, The Bright Boys: A History of Townsend Harris High School (ISBN 0-313-31479-9).

Brian Condon became principal after a heated debate concerning Interim Principal Rosemarie Jahoda, which was covered extensively by student reporters from The Classic.

Over 15,400 students compete for approximately 270 seats in the freshman class each year based on their middle school grades, standardized test scores and attendance records. Admission is available to all New York City residents in the 8th grade. Prior to the COVID-19 pandemic, a minimum grade point average of 91 was required of all applicants to be considered for admission, as well as standardized reading and math scores at a minimum of the 90th percentile (4.3 on both English and Math). Now, post-pandemic, beginning in 2022, students are grouped in tiers based on their final 7th grade core subjects (ELA, Social Studies, Math and Science) averages, with Tier 1, an average greater than 94, having priority for admissions. A short video and a humanities/science essay are also required as part of the application process.

Some seats are available for 9th graders wishing to start Townsend as sophomores, though as the number depends on the number of students who decide to leave the school during freshman year, the number varies significantly from year to year. In 2006, only 5 were available, and in 2019, just 10 seats were available to 5,000 students who applied.

In addition to the standard three-year Regents English program, all students take a "fifth year" of English as freshmen in the form of a "Writing Process" composition course. In addition to the standard modern language requirement which may be fulfilled with classes in Spanish, French, or Japanese, students must meet a two-year classical language requirement which can be fulfilled by classes in Latin or classical Greek. There is also a rigorous physical education requirement, especially in freshman year, and a senior project required of students. A variety of electives and AP classes are also offered to students. As of 2004, AP World History became a mandatory subject and replaced the Regents-level course. Every subject requires students to execute at least one major project a year, with history classes requiring one per semester and English several per semester. These projects are referred to as "collaterals."

In the 2022-23 school year, Townsend Harris offered the following Advanced Placement (AP) classes: Computer Science A, Computer Science Principles, English Language and Composition, English Literature and Composition, Art History, Calculus AB & BC, Statistics, Capstone, Biology, Chemistry, Environmental Science, Physics 1, French Language and Culture, Japanese Language and Culture, Spanish Language and Culture, Spanish Literature and Culture, Macroeconomics, Psychology, United States Government and Politics, United States History, World History: Modern.

The most notable feature of the school's curriculum is the senior "Bridge Year" program. Students in good standing may take up to 12 credits at Queens College at no cost to themselves. This includes an elective course taught by Queens College faculty and a required humanities seminar co-taught by Harris teachers and Queens College faculty. The curriculum and format is fairly similar to the Great Books seminars required of liberal arts freshmen at colleges around the world, with heavy emphasis on critical reading and writing.

Townsend Harris was originally an all boys school, but is now open to all.

As of 2023, the school's population is largely Asian; the 2022-23 school survey showed Asians making up 57% of the student body total, comprising the largest segment of the school's population. White students comprise 16% of the population, Hispanic students 16% and black students 6%.

As of 2024, 60% of students at Townsend Harris are from an economically disadvantaged background.

The school has a 99% graduation rate.

Scores on standardized examinations are also high when compared to other public high schools; in the year 2005–2006, Harrisites had average scores of 628 and 632 on the SAT verbal and math sections, respectively, compared to 551 and 565 for what the city deems "similar schools" and 444 and 467 for students citywide.

• The Blue Ribbon Schools of Excellence Foundation named THHS a 21st Century School of Distinction in June 2004. In December of that year, the school was named a Lighthouse School by the same organization.
• In 2005 and 2006, the school had the highest percentage of students passing Regents exams of any New York City Department of Education high school.
• THHS was awarded with the 2006-2007 Highest Percentage Passing AP World History Scores in the US for a Large School.
• In 2008, Intel awarded THHS with the Intel Schools of Distinction Award in Science Excellence. It was one of three schools, one elementary, middle, and high school, to be awarded such, and one of six to be awarded at all. The schools were each awarded "a $10,000 cash grant from the Intel Foundation and an award package that includes curriculum materials, professional development resources, hardware and software valued at more than $160,000."
• As of 2024, THHS has been awarded with the First Amendment Press Freedom Award six times. Its last of these awards was in 2014. The award celebrates freedom of speech in student publications, in this case, Townsend's The Classic.

This section needs expansion with: Section has been cleaned out; most people once listed here went to Townsend Harris Hall Prep School. You can help by adding to it. (August 2024)

• Neil Drumming, journalist, writer, and director of the film Big Words (2013), and podcast producer for This American Life, Serial, and The New York Times.
• Michael Weiss, journalist; contributing editor at New Lines magazine and senior correspondent for Yahoo News.

• Hari Kondabolu, stand-up comic.

• Divya Narendra, co-founder of SumZero and the now-defunct ConnectU (originally HarvardConnection).

• Nily Rozic, politician and assemblywoman for New York's 25th State Assembly district.

• Townsend Harris High School official website