- Osborne, Stephanie (fl. 2010s) (items) (chron.)
- See www.sff.net/people/steph-osborn
- Osborne, William Hamilton (1873-1942) (items) (chron.)
- See www.jerseyhistory.org/findingaid.php?aid=1137
- Osgood, Irene (c1869-1922) (items) (chron.)
- Born Irene De Belot near Richmond, Virginia; married someone named Osgood, then Charles Piggot Harvey, then Robert Sherard.
- Osgood, Kate Putnam (1841-1910) (items) (chron.)
- See en.wikisource.org/wiki/Author:Kate_Putnam_Osgood
- O’Shaughnessy, Arthur W(illiam Edgar) (1844-1881) (items) (chron.)
- See en.wikipedia.org/wiki/Arthur_O'Shaughnessy
- O’Shaughnessy, Kenneth (fl. 2010s) (items) (chron.)
- See sites.google.com/a/newmyths.com/nmwebsite/contributors/kenneth-o-shaughnessy
- Oshikawa, Shunrō; pseudonym of Masaari Oshikawa (1877-1914) (items) (chron.)
- See en.wikipedia.org/wiki/Shunrō_Oshikawa
- Oshiro, Mark (fl. 2010s-2020s) (items) (chron.)
- See markdoesstuff.tumblr.com
- Osias, Kate (Aton) (fl. 2000s-2010s) (items) (chron.)
- See wishcatcher.blogspot.co.uk
- Osinsky, Valentina (fl. 2020s); used pseudonym Nymphya (items) (chron.)
- See nymphya.com
- Osmeña, Cristina (fl. 1990s-2020s) (items) (chron.)
- See owlhollowpress.com/cristina-osmena
- Ossi, Ijeoma (fl. 2020s) (items) (chron.)
- See www.behance.net/Ijeoma
- Ostojic, Branislav (fl. 2020s); used pseudonym cokacoka (items) (chron.)
- See www.pond5.com/artist/cokacoka
- Ostow, Micol (1976- ) (items) (chron.)
- See en.wikipedia.org/wiki/Micol_Ostow
- Ostrovski, Emil (fl. 2010s) (items) (chron.)
- See www.emilostrovski.com
- Ostrovsky, Andrew (fl. 2010s) (items) (chron.)
- See agsandrew.deviantart.com
- O’Sullivan, Patrick (fl. 2010s) (items) (chron.)
- See patrickcosullivan.com
- O’Sullivan, Vincent (1868-1940) (items) (chron.)
- See modjourn.org/render.php?view=mjp_object&id=mjp.2005.01.028
- O’Sullivan, William J. (1899-1974) (items) (chron.)
- See www.newspapers.com/article/news-press-obituary-for-william-j-osul/128770305
- Otis, Abbey Mei (fl. 2010s) (items) (chron.)
- See www.goodreads.com/author/show/5456552.Abbey_Mei_Otis
- O’Toole, Brian Patrick (1963- ) (items)
- See en.wikipedia.org/wiki/Brian_Patrick_O'Toole
- O’Toole, George J. (1936-2001) (items) (chron.)
- See www.sf-encyclopedia.com/entry/otoole_george
- Ott, Anthony B. (fl. 1940s-1950s) (items) (chron.)
- possibly a pseudonym.
- Ott, [Dr.] John N(ash) (1909-2000) (items)
- See en.wikipedia.org/wiki/John_Ott
- Otto, Mirando (1967- ) (items)
- See en.wikipedia.org/wiki/Miranda_Otto
- Otus, Erol (fl. 1970s-2010s) (items)
- See en.wikipedia.org/wiki/Erol_Otus
- Ouellet, Debbie (fl. 2000s-2010s) (items) (chron.)
- See www.debbieouellet.com
- Ouellette, Pierre (1945- ) (items)
- See www.sf-encyclopedia.com/entry/ouellette_pierre
- Ould, Chris (1959?- ) (items)
- See www.sf-encyclopedia.com/entry/ould_chris
- Oursler, Grace (Perkins) (1900-1955) (items) (chron.)
- Born in Boston; educated at Columbia School of Journalism.
- Outfield, Rish Benjamin (fl. 2010s) (items) (chron.)
- See rishoutfield.blogspot.co.uk
- Outhwaite, Ida Rentoul (1888-1960) (items)
- See en.wikipedia.org/wiki/Ida_Rentoul_Outhwaite
- Over, F. A. Ells; [i.e., Franklin A. Over] (1902-1972) (items) (chron.)
- See tellersofweirdtales.blogspot.com/2023/09/the-eyrie-september-1923.html
- Overholser, Wayne D. (1906-1996) (items) (chron.)
- See en.wikipedia.org/wiki/Wayne_D._Overholser
- Ow, Anya (fl. 2010s-2020s) (items) (chron.)
- See anyasy.com
- Owen, Frank (1893-1968) (items) (chron.)
- See tellersofweirdtales.blogspot.co.uk/2015/06/frank-owen-1893-1968.html
- Owen, James A. (fl. 1970s-2010s) (items) (chron.)
- See jamesaowen.com/
- Owen, Jule (fl. 2010s) (items) (chron.)
- See juleowen.com
- Owen, Paula Arwen; married name of Paula A. Friedlander (fl. 2000s-2020s) (items) (chron.)
- See www.arwendesigns.net
- Owen, Walter (1884-1953) (items)
- See www.sf-encyclopedia.com/entry/owen_walter
- Owen, Wilfred (Edward Salter) (1893-1918) (items) (chron.)
- See en.wikipedia.org/wiki/Wilfred_Owen
- Owens, Derek (fl. 2010s-2020s) (items) (chron.)
- See www.derekowens.net
- Owens, Jim (fl. 1980s-2020s) (items) (chron.)
- See dargonzine.org/author/jowens
- Owens, K. L. (fl. 2010s) (items) (chron.)
- See www.shimmerzine.com/authors/author-page-k-l-owens/
- Owings, Mark (Samuel) (1945-2009) (items) (chron.)
- See www.sf-encyclopedia.com/entry/owings_mark
- Owomoyela, An (fl. 2000s-2020s) (items) (chron.)
- See an.owomoyela.net
- Owton, Martin (1958- ) (items) (chron.)
- See www.martinowton.com
- Oyebanji, Adam (fl. 2020s) (items)
- See adamoyebanji.com
- Oyèkànmí, Sodïq (fl. 2020s) (items) (chron.)
- See strangehorizons.com/author/sodiq-oyekanmi
- Ozawa, Hisashi (fl. 2010s) (items) (chron.)
- See kcl.academia.edu/HisashiOzawa
- P., Natasha T-Z. (fl. 2010s) (items) (chron.)
- See www.aziot.deviantart.com
- Pablo, Jose Luis (fl. 2010s-2020s) (items) (chron.)
- See joseluisbpablo.wordpress.com
- Pacat, C(atherine) S. (fl. 2010s) (items)
- See en.wikipedia.org/wiki/C._S._Pacat
- Pace, Guy L. (fl. 1970s-2010s) (items) (chron.)
- See guypace.com
- Pace, Richard (fl. 1990s-2010s) (items) (chron.)
- See richardpace.daportfolio.com
- Pace, Tom; [i.e., Thomas C. Pace, Sr.] (1929-2008) (items) (chron.)
- Born in Florida, graduated from Georgia Tech.; working for aircraft firm.
- Pacella, Chukwuma-Eke (c2005- ); used pseudonym the_people (items) (chron.)
- See strangehorizons.com/author/chukwuma-eke-pacella
- Pachico, Julianne (fl. 2010s) (items)
- See www.juliannepachico.com
- Pachter, Josh (1951- ) (items)
- See joshpachter.com
- Pacione, Nickolaus Albert (1976- ) (items) (chron.)
- See www.goodreads.com/author/show/3292495.Nickolaus_Pacione
- Packard, Edward (1931- ) (items)
- See www.sf-encyclopedia.com/entry/packard_edward
- Pacotti, Sheldon J. (fl. 2010s-2020s) (items) (chron.)
- See sheldonpacotti.com
- Paddock, Jilly (fl. 2010s) (items) (chron.)
- See www.goodreads.com/author/show/5624332.Jilly_Paddock
- Padilla, Ignacio (1968-2016) (items) (chron.)
- See en.wikipedia.org/wiki/Ignacio_Padilla
- Pagan, David D. (fl. 2010s) (items) (chron.)
- See davidpagan.wordpress.com
- Page, Gerald W(ilburn) (1939- ) (items) (chron.)
- See en.wikipedia.org/wiki/Gerald_W._Page
- Page, Laura (fl. 2010s) (items) (chron.)
- See laurapage.net