Conductor Seiji Ozawa will set down the baton for six months.
"I am perfectly fine right now. I have no problems drinking or eating," the 74-year-old maestro said at a news conference in Tokyo.
Ozawa's taking a break because he's been diagnosed with esophageal cancer.
The Associated Press reports the doctor who accompanied Ozawa to the press conference said the cancer is in an early stage. "I will abide by the doctors' advice. I will be back within six months," Ozawa said.
Ozawa is currently chief conductor of the Vienna State Opera. He took the post in 2002, and his tenure is set to expire in June. His 30 concerts home and abroad from January to June 2010 will be cancelled.
"Our thoughts and best wishes go to Seiji Ozawa," Ioan Holender, the director of the opera, said in a statement.
Before conducting the Vienna opera, the Japanese conductor served 29 years as music director of the Boston Symphony Orchestra. He is also the artistic director and founder of the Saito Kinen Festival, a music and opera festival in Japan.
The Saito Kinen said it was hoping for Ozawa's swift return. "We appreciate his passion for music," a festival official told The AP. "We are eagerly waiting for his comeback."