The Unefra system was a planetary system in Cardassian space near the Cardassian-Romulan border.

Enabran Tain maintained a safe house on Unefra III. Elim Garak and Odo came to the Unefra system in 2371 aboard the runabout USS Mekong to search for him. There, they were captured by Tain's Romulan warbird. (DS9: "Improbable Cause")

The Unefra system is probably located in the Algira sector.
According to Star Trek: Star Charts (p. 46) and Stellar Cartography: The Starfleet Reference Library ("Federation Historical Highlights, 2161-2385"), the Unefra system was located in the Alpha Quadrant. The system's primary was a F-class star.