Jesse David Armstrong (born 13 December 1970) is an English screenwriter and producer. Known for writing for a string of several critically acclaimed British comedy series as well as satirical dramas, he has received numerous accolades, including two BAFTA TV Awards, three Golden Globe Awards, three WGA Awards, and eight Emmy Awards in addition to nominations for an Academy Award and two BAFTA Film Awards.

He first gained prominence co-creating the British comedy shows Peep Show (2003–2015) and Fresh Meat (2011–2016) with his writing partner Sam Bain. During this time, he wrote for the political satire series The Thick of It (2005–2009) and co-wrote In the Loop (2009), the latter of which earned him Academy Award and BAFTA nominations for Best Adapted Screenplay. He also co-wrote the films Four Lions (2010) and Downhill (2020). Armstrong wrote and directed the television film Mountainhead (2025).