The little owl Athene noctua (Scopoli, 1769) is a small raptor that is widely distributed from northern to southern Portugal and several other countries in Europe, Asia and North Africa, and which has been introduced into New Zealand. In the current study, 18 fecal samples were collected from little owls kept at the Lisbon Center for Wild Animal Recovery, which is located in Monsanto Forest Park, Lisbon, Portugal. Twelve (67%) of them were found to be passing an undescribed species of Avispora in their feces. The oocysts of Avispora mochogalegoi n. sp. were ellipsoidal with a bilayered wall and measured 38.9 × 32.9 µm, with a shape index of 1.18. No micropyle, oocyst residuum or polar granule was present. The sporocysts were subspherical, measuring 21.1 × 20.1 µm. Stieda, sub-Stieda and para-Stieda bodies were absent. The sporocyst residuum was composed of a compact subspherical mass of granules. This is the fourth species of Avispora reported in Strigiformes.