Wagna is a municipality in the district of Leibnitz, in the Austrian state of Styria. It lies in the southern part of the region, near the town of Leibnitz.
The area is notable for its connection to the ancient Roman town of Flavia Solva, which stood near what is now Wagna. Flavia Solva was a Roman settlement in the province of Noricum, and its remains are located in the municipality's vicinity.