A sweeping reorganization of the Chinese government was approved yesterday by the Standing Committee of the National People's Congress, or parliament, to reduce the congested bureaucracy here and bring in younger leaders.

The number of vice premiers was cut from 13 to 2, dozens of independent commissions and bureaus were merged into larger ministries and 23 new ministers were appointed. The changes reduce by two-thirds the 1,000-plus ministers and vice ministers at the top of the governmental pyramid here, and the total staff reduction is expected to be about one-third of the central government's present level.

The two vice premiers now are Wan Li, 66, a former governor and Communist Party leader of Anhui Province, and Yao Yilin, 65, who has headed the State Planning Commission. Premier Zhao Ziyang, Wan and Yao are expected to divide day-to-day supervision of the government. Moscow Rejects June Summit

MOSCOW--A senior Soviet spokesman ruled out a U.N. meeting next month between Soviet President Leonid Brezhnev and President Reagan and said the Kremlin was holding out for a "prepared" summit in Europe this fall.

"We are waiting for a clear and accurate reply from the American president" on Brezhnev's summit proposal, Yuri Zhukov, the leading commentator of the Communist Party newspaper Pravda, told a news conference.