Deniz Tek (born November 10, 1952) is an American singer, guitarist and songwriter and a founding member of Australian rock group Radio Birdman. He has played in many of the underground rock bands of the 1970s, including Australian bands The Visitors and New Race, but is most known for exerting his burning Detroit-style guitar influence over the punk rock genre in Australia.

Tek has Turkish origins but was born and raised in Ann Arbor, Michigan, United States. He spent 1967 in Sydney with his family and was greatly attracted to the Australian landscape, moving there permanently in 1972 to commence his medical studies at University of New South Wales in Sydney. Tek is a trained ER doctor and ex-navy flight surgeon who currently splits his time working in emergency departments in hospitals in New South Wales and Hawaii while still taking time to record and tour.