Chinese shares rallied on Wednesday as expectations ran high for new reform measures ahead of the annual parliamentary session slated to open on Thursday.

The benchmark Shanghai Composite Index moved up 0.51 percent to finish at 3,279.53 points. The Shenzhen Component Index advanced 1.12 percent to close at 11,655.08 points.

Investors were keeping an eye on the third session of the 12th National People's Congress (NPC). At the opening meeting of the NPC session on Thursday, Premier Li Keqiang will reveal this year's GDP target while delivering the government work report.

China's economy grew 7.4 percent last year, its slowest pace in 24 years.

The ChiNext Index, tracking China's Nasdaq-style board of growth enterprises, gained 2.45 percent to close at a record high of 2,009.83 points.

"It was a highlight on Wednesday's stock market," said Sun Xiwei, chief investment advisor with CITIC Securities. "The index stayed above the 2,000-point mark for most of the day and finished at a record high."

Sun added that stocks on the ChiNext board are mostly in the country's emerging industries, which represent the economy's growth potential.