Ichiro Maruyama (22 May 1928 – 27 April 2013), who wrote under the pen name You Sano, was a Japanese mystery writer and critic.
In 1953, he graduated from the University of Tokyo Department of Psychology and began work as a part-time writer in Hokkaido for Yomiuri Shimbun.
He produced over a thousand short stories, many of which were made into bunko, but the introduction of a consumption tax led to price revisions, and many publishers stopped printing them.
Jugo Kuroiwa criticized his writing and described it as "novels that do not shed blood and sweat", that go through mystery as an intellectual game but in which, on the other hand, the patterns of work repeatedly become mannered, eliminating eccentric and large-scale crimes, creating realism and a characteristic moderation.
The group later included Saho Sasazawa, Haruhiko Oyabu, Michio Tsuzuki, Jiro Ikushima, and Masako Togawa.