China's polysilicon imports jumped during the first eight months of this year but prices slid, further squeezing profit margins for domestic producers, official data have indicated.

China imported 56,000 tons of polysilicon, a raw material used to make solar cells, from January through August, up 32.8 percent year on year, with import prices averaging $26.92 per kg, down 54.2 percent compared with last year's average, according to a statement posted on the website of the General Administration of Customs.

South Korea, the United States and Germany accounted for 87.8 percent of China's polysilicon imports in August.

The average import prices from South Korea and Germany fell from the previous month to $23.33 per kg and $29.1 per kg, respectively, according to the statement.

China has been suffering from an overcapacity of polysilicon following massive investment in the sector after prices peaked four years ago.

Customs data showed that China only exported 166 tons of polysilicon in August, bringing total exports in the first eight months of this year to 897 tons, mainly due to waning demand in Europe.