Hong Kong stocks also climbed, after a strong rally in Wall Street, as investors near an expected U.S. rate hike, the first in nearly a decade.
China's CSI300 index rose 0.5 percent, to 3,694.14 points by lunch break, and the Shanghai Composite Index gained 0.4 percent, to 3,539.04 points.
An avalanche of data in coming weeks is likely to show China's economic performance remains sluggish, reinforcing expectations that Beijing will carry out more stimulus measures in months ahead.
Investors are apparently making their bets on sectors that would benefit from a government-engineered economic restructuring.
Such conviction was bolstered by Premier Li Keqiang's vow to ruthlessly deal with "zombie" firms, which are generally understood to be loss-making companies in sectors such as coal-mining and steel-making.
Shenzhen's start-up board ChiNext, which hosts many of China's hi-tech firms, jumped nearly 2 percent, while an index tracking major healthcare companies advanced 2.4 percent.
Beijing Tongrentang, a Shanghai-listed maker of traditional Chinese medicine, jumped the maximum allowed 10 percent.
But property plays – which represent China's old growth model – pulled back sharply after last week's rebound triggered by a 33 percent surge for China Vanke Co.
On Monday, Vanke slumped more than 4 percent, after disclosing that last week's jump was the result of Shenzhen Jushenghua Co buying additional shares, and becoming Vanke's top shareholder.
Brokerages shares also underperformed, amid fears that regulators would widen probe into the industry.
CITIC Securities fell 1.3 percent. The company said on Sunday that it was not able to contact two of its top executives, following media reports that they had been asked by authorities to assist in an investigation.
In Hong Kong, the Hang Seng index added 0.4 percent, to 22,327.99 points, the Hong Kong China Enterprises Index gained 0.3 percent, to 9,866.52.
Energy was the only main sector that fell in morning trading. Investors sold shares in oil giants CNOOC, PetroChina and Sinopec on worries that global oil prices could continue sliding.