The southern province of Guangdong, whose economic output exceeded 3.5 trillion yuan ($512.1 billion) this year, remains China's economic powerhouse, a report said on Wednesday.

The report, released by the Guangdong Academy of Social Sciences, said other provinces, regions and municipalities are unlikely to replace or overtake Guangdong in economic output in the near future.

Guangdong's economic output this year is expected to be at least 500 billion yuan more than that of Shandong or Jiangsu provinces, which ranked second and third last year, according to the report.

Guangdong was an agricultural province before China launched the reform and opening-up drive in 1978. At that time, its economic output was about 20 billion yuan, or 5 percent of the national economy.

However, it grew at an average annual rate of 13.45 percent in the past three decades, 3.5 percentage points higher than the national level, and accounted for one-eighth of the national economy last year.