Food habits, nutrient preferences, and roost variations of Indian flying fox Pteropus giganteus were investigated for a period of 1 year in two public parks in Lahore, Pakistan. Bolus and guano samples of P. giganteus were collected on a monthly basis, and seeds of 32 plant species belonging to 23 genera and 15 families were identified from the ejecta samples. Of these 32 food species, 8 were native and 24 were exotic; 13 were commercially important, while 19 species had no mercantile value. Proximate analysis of the food items revealed that fruits with comparatively higher moisture content were utilized during summer; fruits having relatively higher carbohydrates, fibers, protein, fats, phosphorous, iron, and sodium were used during winter; diets having relatively greater calcium and vitamin C contents were used during autumn; and phosphorous-rich diets were used during spring. Permanent roosting trees (n = 50) representing 17 families, 19 genera, and 21 species were monitored to record the abundance and roost fidelity of P. giganteus. The maximum number of bats (n = 425) was recorded for Dalbergia sissoo during summer, Kigelia pinnata (n = 270) during spring, Celtis australis (n = 374) during autumn, and Cedrela toona (n = 330) during winter.