Hideki Matsutake (born August 12, 1951 in Yokohama, Kanagawa Prefecture, Japan) is a Japanese composer, arranger, and computer programmer. He is known for his pioneering work in electronic music and particularly music programming, as the assistant of Isao Tomita during the early 1970s and as the "fourth member" of the band Yellow Magic Orchestra during the late 1970s to early 1980s.
Through his participation in the session recording of Ryuichi Sakamoto's 1978 album Thousand Knives, he joined the recordings of Yellow Magic Orchestra during 1978-1982 as their sound programmer, to become known as "the fourth member" of the group. In 1981, he formed a unit of his own under the name Logic System, which released its latest album in 2008. He also continued to take part in solo activities by YMO members such as Haruomi Hosono and Yukihiro Takahashi beyond the group's breakup in 1983. He was also a member of the video game music group Akihabara Electric Circus in 1988 and composed music for the 1996 video game Guardian Heroes. Today, Matsutake is also Chairman of Japan Synthesizer Programmers Association (JSPA).