Mark Oshiro (born October 23, 1983) is an American author, editor, and activist based in Atlanta, Georgia. They write young adult and middle grade fiction books, often exploring themes of identity, belonging, and family. They were a Hugo-nominated writer for the online Mark Does Stuff universe in 2013 and 2014, where they analyze books and TV series. Their 2018 young adult novel, Anger Is a Gift, was a nominee for the 2019 Lambda Literary Award for LGBTQ Children's/Young Adult and won the 2019 Schneider Family Book Award. They are co-author of The Nico di Angelo Adventures series with Rick Riordan.