Ken Takeuchi is a Japanese voice actor born on February 20, 1978, in Tokyo, Japan. He is a graduate of the Japan Narration Acting Institute and is affiliated with the talent management firm ARTSVISION. Takeuchi began his voice acting career in the early 2000s, with one of his debut roles being a main character in the video game Photogenic in 2000.

Takeuchi has built a career portraying a wide range of characters across anime, video games, and drama CDs. In anime, he is known for several prominent roles. He voiced the protagonist Keita Suminoe in the romantic comedy series Kiss×sis and its original video animations. He played the role of Louis Asahina in the 2013 anime Brothers Conflict. He is also recognized for voicing Lithuania in the long-running and popular series Hetalia, starting with Hetalia: Axis Powers in 2009 and continuing in later installments like Hetalia The World Twinkle.

His other television anime credits include Yusuke Takazaki in Green Green (2003) and its OVA Green Green: Erolutions, Ranmaru Miura in Hoop Days (known in Japanese as Dear Boys), and Count Leonare in Kuromajyo-san ga Tōru!!. He has also appeared in series such as Black Cat as Kevin McDougal, Loveless as Kio Kaido, and the 2016 anime Haven't You Heard? I'm Sakamoto as Mario.

Beyond anime, Takeuchi has an extensive body of work in video games and drama CDs. His game credits include roles such as Louis Haidweger in Absolute Obedience and Kazusa Takashina in the photographic series "Campus". He has also participated in mobile games like Boyfriend (Kari) as Kuon Amemiya and Granblue Fantasy as Anatoly. In the realm of drama CDs, he has been highly active, particularly in the Boys Love genre, with notable performances in series like "Hana no Mizo Shiru" and collaborations with actors such as Yuuki Ono.