Janusz Korczak, the pen name of Henryk Goldszmit, was a Polish Jewish educator, children's author and pedagogue known as Pan Doktor or Stary Doktor. After spending many years working as a principal of an orphanage in Warsaw, he refused sanctuary repeatedly and stayed with his orphans when the entire population of the institution was sent from the ghetto to the Treblinka extermination camp during the Grossaktion Warschau of 1942.

Janusz Marek Kurtyka was a Polish historian, and from December 2005 until his death in the 2010 Polish Air Force Tu-154 crash, the second president of the Institute of National Remembrance (IPN).

Janusz Leon Wiśniewski is a Polish scientist and writer mostly known for his novel S@motność w Sieci translated into English as Loneliness on the Net.

Janusz Meissner was a Polish writer and journalist, and a pilot of Polish Air Force.

Janusz Piekałkiewicz was a Polish underground soldier, historian, writer, as well as a television and cinema director and producer. He was a world-renowned author on many aspects of World War II history; over 30 of his books have been printed, most of them in German, and later translated to other languages. He also wrote from his experiences during the war and specialized in detailing operations within the secret services. A unique characteristic of many of his books is that chapters contain two parts. Firstly, he describes details and contemporary quoted sources and then, in the second part, he provides analysis and his own commentaries to those events. According to critics, this results in a very objective presentation of the material. In addition to his well-known history books, he also wrote books about treasure hunting.

Janusz Przymanowski (1922–1998) was a Polish translator. He wrote the novel Four Tank-Men and a Dog.

Janusz Tazbir was a Polish historian, specializing in the culture and religion of Poland in the 16th and 17th centuries. He was the Polish-side Chairman of German-Polish Textbook Commission from 1991 to 1997.

Janusz Andrzej Zajdel was a Polish science fiction author, second in popularity in Poland to Stanisław Lem. His major genres were social science fiction and dystopia. His main recurring theme involved the gloomy prospects for a space environment into which mankind carried totalitarian ideas and habits: Red Space Republics, or Space Labor Camps, or both. His heroes desperately try to find meaning in the world around them.

Jan Willem Lincoln "Janwillem" van de Wetering was the author of a number of works in English and Dutch.

Janysh Osmonovich Kulmambetov is a Kyrgyz writer-screenwriter, playwright, stage and film director, screenwriter, producer, editor, journalist, and theater critic.