Oliver Siebeck is a established German voice actor, born in 1961 in Wanne-Eickel, Germany, who has lent his voice to numerous characters in anime and live-action series for German-language audiences. His career spans several decades, with active voice work documented from at least the early 2000s through the 2020s. He is widely recognized in the anime community for providing the German voice for the iconic character Vegeta in the Dragon Ball franchise, a role he has performed for over 200 episodes of the television series and in several films. His portrayal of Vegeta continued in the theatrical releases of Dragon Ball Super: Broly and Dragon Ball Super: Super Hero, where he was part of a concerted effort to reunite the original German voice cast from the Dragon Ball Z era.

Beyond this signature role, Siebeck's voice work encompasses a wide variety of characters in both anime films and series. In the film Black Fox, he voiced the character Brad. He took on the role of the antagonist Lord Bondrewd in the feature film Made in Abyss: Dawn of the Deep Soul. His other notable anime roles include Dimsdale Boiled across the three Mardock Scramble films, Elhart in The Rising of The Shield Hero, Gilria in Kikou Keisatsu Metal Jack, and Akira Mitani in Brave Story. His early anime work includes voicing characters in series such as Spezialeinheit Metal Jack and Detektiv Conan in the early 2000s.

Throughout his career, Siebeck has frequently collaborated with a consistent group of fellow German voice actors. Industry data indicates his most frequent collaborator is Tilo Schmitz, with whom he has worked on numerous projects. Other voice actors he has often worked alongside include Rainer Fritzsche, Jan Spitzer, and Tommy Morgenstern, the German voice of Son-Goku, further solidifying their association with the Dragon Ball series. His work is primarily in dubbing, contributing to the German-language versions of international productions across film and television.