Abstract: Nestling food composition and consumption of great tits (Parus major Linnaeus) in the Poplar plantation was studied using 230 preys collected from the nestling crops at Yihe Forest Farm, Yinan County, Shandong Province during May to July in 1991. The average food consumption amounted to 1377.6 preys per clutch and 1294.9 preys per ha in May, 1002.2 preys and 310.8 preys in June, 1383.3 preys and 864.7 preys in July. Based on the nestling food composition, the food selection of breeding great tits was discussed preliminarily combining with the sample data of insects taken from the branches and frass in the Poplar plantation. Changes in insect species and numbers showed changes in diet from May to July. More pupae and larvae of Apatura metis Freyer were found in May, more adults of Lymantridae and Parathrene tabaniformis Rottenberg in June, and more insect species in July.