Yacka is a small settlement in the shallow valley of the Broughton River in mid-north of South Australia. There is a war memorial beside the old State Bank of South Australia building. There is also a nine-hole golf course. At the 2006 census, Yacka had a population of 208.
Yacka is where the Horrocks Highway (Main North Road) crosses the Broughton River midway between Clare and Gladstone. It was also on the Gladstone-Balaklava railway, built as narrow gauge in 1894 and converted to standard gauge in 1927. The railway closed by 1993.
The town name is probably shortened from Yackamoorundie Creek and derived from a native name for the place.