Forest area of Turkey is 22.6 million hectares, which constitutes 28.8% of the overall land area. 47% of the forests is coniferous, 32% is broad-leaved tree species and 21% mixed species. The Scale insects (Hemiptera: Coccomorpha) are cryptic and mostly invisible insects which are mostly small less than 5 mm long. Many scale insects are economically important pests of agriculture, horticulture, and forestry. Around 400 scale insect species are known in Turkey, totally 119 Coccoidea species are fed on forest trees and shrubs; among 45 species of them on conifers and 74 species on broad-leaves trees and shrubs. Marchalina hellenica Gennadius (Marchalinidae) is a famous and economically important species that resourced honeydew honey called "pine honey". This study examines scale insects, their distribution, host plants, natural enemies, damages, and role of forest biodiversity in Turkey.