The secretary's visit to Asia, the fourth in less than a year, will follow a group meeting with his Southeast Asian counterparts in Hawaii April 1-3.
He will first travel to Tokyo and then head to Beijing.
"In China, the secretary will have a full complement of bilateral engagements focusing on our military-to-military relationship and on regional security issues," Rear. Adm. John Kirby, Pentagon press secretary, told reporters. "The secretary views this relationship as crucial to our rebalance, and he will emphasize the importance of building trust, increasing openness and transparency and upholding international norms throughout his trip."
Kirby did not specify how long Hagel will stay in China.
In Beijing, a Chinese Defense Ministry official said he will make a four-day trip there starting April 7.
His final destination will be Mongolia, which has increased its role in global security, shown in its deployment of troops to Iraq and Afghanistan as well its participation in peacekeeping operations worldwide.
A Pentagon source said Hagel tried hard to include Seoul in his itinerary.
"As South Korea is an ally of the United States, the secretary sought to make even a brief stop there, but he couldn't do so due to a tight schedule in China," the source told Yonhap News Agency.
It's quite unusual for a U.S. defense chief to bypass the home to 28,500 American troops while traveling to Northeast Asia.
Secretary of State John Kerry stopped in Seoul and Beijing, bypassing Tokyo, in his latest regional tour in February, the source noted.
Hagel last visited Seoul in October for annual talks with South Korean Defense Minister Kim Kwan-jin.