After spending his youth in New Zealand, he graduated with a bachelor in product design in Auckland. In 1999 during his study, he moved to Paris for a scholarship study at ENSCI / Les Ateliers. In 2003 he returned to Japan and since 2005 he worked as a designer at Naoto Fukasawa Design ltd in Tokyo. In 2012 Takeuchi decided to set up a satellite office for Fukasawa in Milan.
In late 2015 he established KEIJI TAKEUCHI SRLS in Milan. Today Takeuchi collaborates with various prestigious brands such as Boffi, De Padova, Living Divani, Geiger / HermanMiller, Ligne Roset, Fredericia and others.