Isospora bors n. sp. (Apicomplexa: Eimeriidae) is described from 6 of 30 (20%) Baiuch rock gecko Bunopus tuberculatus Blanford in Saudi Arabia. Sporulated oocysts are subspheroidal to spheroidal, 18 × 16 (17-20 × 15-17) μm, with a bilayered, smooth, yellow-orange wall, without striae or micropyle. Polar body and oocyst residuum, both absent. Sporocysts are ovoidal, 10 × 7 (9-11 × 6-9) μm, with a Stieda body and sporocyst residuum. Endogenous stages developed in the cytoplasm of epithelial cells of the small intestine and above the host cell nucleus.