Great Tits are primarily insectivorous in the summer, feeding on insects and spiders which they capture by foliage gleaning.[18] Invertebrate prey taken include cockroaches, grasshoppers and crickets, lacewings, earwigs, bugs (Hemiptera), ants, flies (Diptera), caddis flies, beetles, scorpion flies, woodlice, harvestmen, bees and wasps, snails and woodlice.[7] During the breeding season, the tits prefer to feed protein-rich caterpillars to their young. Nestlings also undergo a period in their early development where they are fed a number of spiders, possibly for nutritional reasons. In autumn and winter, when insect prey becomes scarcer, Great Tits add berries and seeds to their diet. Seeds and fruit usually come from deciduous trees and shrubs, and include the seeds of beech and hazel. Where it is available they will readily take table scraps, peanuts and sunflower seeds from bird tables. In particularly severe winters they may consume 44% of their body weight in sunflower seeds. They often forage on the ground, particularly in years with high beech mast production.

In England, Great Tits learned to break the foil caps of milk bottles delivered at the doorstep of homes to obtain the cream at the top.

Listen to the bird song of the Great Tit