In 1987, he entered Britain's Royal Ballet School (RBS). In 1988, he became the first Japanese dancer to perform at the Mariinsky Theatre in Saint Petersburg. In 1989, he was the first Japanese dancer to receive the gold medal at the Prix de Lausanne. He also received a golden prize at the European Young Dancer of the Year competition held in Paris. That same year, he joined the Britain's Royal Ballet Company (RBC) as the company's first Asian, and became the youngest soloist in its history. He became Principal in 1993. While he was with the RBC, he also made guest appearances in other ballet company performances such as the Bolshoi Ballet's Giselle. Between 1996 and 1998, he produced and starred " Made in London. "
After he left the RBC in 1998. K-BALLET COMPANY was founded by Tetsuya Kumakawa、 Principal dancer, choreographer, and artistic director, the next year in 1999. He produced his own versions of "Giselle",'The sleeping beauty" ,"Swan LAKE", "Coppelia", "Don Quixote" ,"The Nutcracker", "Le Corsaire", "Romeo and Juliet', "Cinderella" and the 15 th anniversary production "La Bayadere" would be a world premiere In March 2014.
In 2004, the company performed Ashton's "Rhapsody "at the Metropolitan Opera House in New York. Kumakawa also created "Beethoven Symphony N0.9,"Wolfgang","Passing Voice", "Solitude", and "Simple Symphony" in 2012.
In 2012,he was invited to be the Artistic Director for the Bunkamura Orchard Hall ,Tokyo.
He opened K-BALLET SCHOOL in 2003,which is a professional classical Ballet School in Japan and is the official associated school of the K-BALLET COMPANY.K-BALLET SCHOOL has been educating younger dancers with his own method and has been cultivated its environment for ballet education in Japan.
He founded also a junior ballet company, K-BALLET YOUTH in 2012,and is giving the younger dancers the best possible education to equip them for a career in the world of dance.
In 2004, Kumakawa received the 3rd Asahi Performing Arts Award for his Choreography and Performance In Swan Lake .In 2005, he received the 55 th Minister of Education, Culture, Sports, Science and Technology's Art Encouragement Prize of Dance. In 2006, K-BALLET COMPANY received the 5 th Asahi Performing Arts Award for its performance of "Don Quixote" and "The Nutcracker"
in 2013,he received the Shijyu hosho(medal of honor with purple ribbon)