SOUTH Australia has harvested its second largest grain crop on record.

Primary industry officials said today the crop would yield 7.83 million tonnes, compared to the record crop of 9.4 million tonnes in 2002.

Spokesman Dave Lewis said lower grain prices and some hot weather in November had taken the edge of what would have been an even better result for farmers.

"We continue to recognise that despite the bumper crop, not all areas of the state have done well this year and those farmers are continuing to face challenges," he said.

Mr Lewis said the 2010 crop was 25 per cent higher than South Australia's 10-year average.