Jirō Tsunoda, born on July 3, 1936, in Tokyo, is a Japanese manga artist with a career spanning from the mid-1950s to the present day. He is the second of eight brothers, and his younger brother, Hiro Tsunoda, is a pop musician. Tsunoda made his professional debut in 1955 with the work Shin Momotarō, published in the magazine Manga Shōnen. Early in his career, he was a frequent visitor to the Tokiwa-sō apartment building, a famous residence for manga artists, where he became close friends with Fujiko Fujio A and interacted with the influential Osamu Tezuka.

Tsunoda first achieved mainstream success in the late 1950s and early 1960s with works in the shōjo (girls' manga) genre, including the series Rumi-chan Kyōshitsu in 1958. For his shōjo manga Bara-iro no Umi, he received the Kodansha Children's Manga Award in 1961. Following this period, his focus shifted to shōnen (boys' manga) magazines, where he created a variety of works ranging from gag manga to sports series. His gag manga Ninja Awate-maru, serialized from 1965 to 1968, was adapted into the anime television series Pyunpyunmaru in 1967.

During the early 1970s, Tsunoda became known for illustrating sports manga based on scripts by writer Ikki Kajiwara. The most notable of these was Karate Master, serialized in Weekly Shōnen Magazine from 1971 to 1973, which became a major hit. This series was later adapted into an anime. From the 1970s onward, Tsunoda developed a strong interest in the occult and paranormal themes, which became a defining characteristic of his subsequent work. His two most famous series from this period are the horror manga Kyōfu Shinbun, serialized from 1973 to 1975, and the supernatural series Ushiro no Hyakutarō, serialized from 1973 to 1976. Both were later adapted into other media, including live-action films and anime.

Throughout his long career, Tsunoda's artistic identity has been marked by significant stylistic versatility, moving from shōjo romance to gag comedy to sports drama before finding a lasting niche in horror and occult storytelling. His notable original works include not only the titles adapted into the anime Hana no Zundamaru, Karate Master, Kyōfu Shinbun, Pyunpyunmaru, and Ushiro no Hyakutarō but also a vast body of manga such as Black-dan, Bōrei Gakkyū, and Megido no Hi. He continued to revisit his popular series with sequels like Shin Ushiro no Hyakutarō and Kyōfu Shinbun II in the 1980s and 1990s. His significance in the manga industry lies in his enduring popularity across multiple genres and his pioneering role in establishing horror and occult manga as a mainstream genre in Japan.