Oak honey is a honeydew honey type. In this study, investigated the source of oak honey and questioned whether it was insect source or extrafloral source. For this purpose, oak species samples were collected from the regions, where the oak honey was produced intensely, in 2016 and 2017. In addition, insect species producing secretion on tree fragments for two years have been observed and studied. Trunk, leaf and fruit parts were taken from oak trees with dark brown secretion. In these samples, anatomical studies have been done to find both the secretion source and is there any damages in the tree tissues due to insect source. Two types of method were followed for the anatomical investigations. Also chemical composition of oak secretion was determined by GC-MS. As a result of study has shown that Quercus frainetto Ten. fruits have got a great number of secretory glandular trichomes and these trichomes produces sweet secretions. In addition to this, GC MS chemical substance analyses of the oak secretion revealed alcohols, aldehydes, aromatic acids, aromatic compounds, carbohydrates, carboxylic acids and their esters, fatty acids and other compounds.