Kohei Yoshiyuki (吉行耕平 , born 1946) is a Japanese photographer

Kohei Yoshiyuki (吉行耕平 , born 1946) is a Japanese photographer who attracted much attention in 1979 with his exhibition "Kōen" (公園, Park) at the Komai Gallery, Tokyo. The black-and-white photographs were presented in a book published in 1980 that is "nominally a soft-core voyeur's manual", with photographs of people in sexual activities in Shinjuku andYoyogi parks (both in Tokyo), mostly with unknown spectators around them. The photographs were taken with a 35 millimetre camera and infrared flashbulbs. Gerry Badger and others have commented on how the photographs raise questions about the boundaries between spectator, voyeur and participant.

Yoshiyuki's works are in the collections of the Museum of Modern Art (New York), San Francisco Museum of Modern Art, Museum of Contemporary Photography (Chicago), Museum of Fine Arts(Houston), and North Carolina Museum of Art (Raleigh).

Shot in three Tokyo parks during the early seventies, The Park is a series of black and white photographs capturing couples meeting up for clandestine trysts and, more provocatively, the voyeurs who came out to watch them. First exhibited in 1979 at Komai Gallery in Tokyo, the uproar surrounding his methods caused these photographs to be hidden from the public for the next 28 years. 

Mr. Yoshiyuki first stumbled upon this hidden world while photographing skyscrapers in front of Chuo Park in Shinjuku at night when he witnessed a couple having sex and quickly discovered an entire scene of young lovers—and their peepers. He soon returned with an inconspicuous 35mm camera, a filtered flash and infrared film, and began shooting these hetero- and homosexual couplings, along with their spectators lurking in the bushes.

What is particularly striking about this series of photographs is not the graphic nature of the sexual acts portrayed, which are usually obscured by other figures or occur out of frame, but the densely packed tableaux of voyeurs who crowd in on the couples and sometimes attempt to join in. The raw, snapshot-like quality of these images implicates photographer, viewer and subject, which makes this work especially poignant and intriguing. In the tradition of Walker Evans on the New York subway or Weegee’s photographs of couples in the movie theatre, Yoshiyuki’s The Park is a social documentary of Japan in the 1970s that is rarely seen or heard of, as well as being a comment on photography itself. As Martin Parr writes in The Photobook: A History, Volume II, “The Park is a brilliant piece of social documentation, capturing perfectly the loneliness, sadness and desperation that so often accompany sexual or human relationships in a big, hard metropolis like Tokyo.”