Obata was born and raised in San Francisco. Due to his family's Japanese heritage, he was nearly interned with other Japanese-Americans during World War II. Though his family was sent to an internment camp, he avoided it by leaving the School of Architecture at the University of California, Berkeley, to study architecture at the School of Architecture at Washington University in St. Louis, the only university in the United States willing to accept Japanese nationals at that time. He earned his bachelor of architecture degree there in 1945.
He then studied under master Finnish architect Eliel Saarinen at the Cranbrook Academy of Art in Bloomfield Hills, Michigan, receiving his master's degree in architecture and urban design in 1946.
After serving in the U.S. Army from 1946 to 1947 and working as an architect in the Chicago office of Skidmore, Owings and Merrill from 1947 to 1951, Obata returned to St. Louis in 1951 to join the firm of Minoru Yamasaki (who would later design the World Trade Center towers), another Nisei architect. Four years later, in 1955, he joined architects George Hellmuth and George Kassabaum in establishing the St. Louis-based architecture firm Hellmuth, Obata and Kassabaum.
Due in part to Obata's prowess and growing reputation, the firm achieved global renown, and Obata himself has won numerous awards for his designs. Today, HOK has more than 1,800 employees in 23 offices worldwide.
In 2010, Obata was featured in a book written by Marlene Ann Birkman and published by The Images Publishing Group titled, Gyo Obata: Architect | Clients | Reflections.[6] The book features 30 of Obata's projects (and clients) spanning five decades.
Obata's design philosophy is "to provide spaces which are not only functional, but also enhance the quality of life for those who work and live in them."[7] In Gyo Obata: Architect | Clients | Reflections, he says that, "The language that architects use to define space is daylight. Each project offers new potential for discovery, for understanding the site and program, and an opportunity to do a thoughtfully designed building that will bring meaning and enjoyment to the people who will occupy it."[6]