Abstract: Volcanic rocks of the Pontides are widespread in the Sinop area. The rocks are mainlymade up of volcanic conglomerates, flow-breccias, pillowlavas, dikes and also associated with them arelava flows and rarely tuffs.Volcanic rocks have basaltic and andesltic compo sition and consist mainly of augite, enstatite, olivine,biotite, plagioclase and analcime. Chlorite, zeolite, prehnite, calcite and opaque minerals are found assecondary minerals.Rocks showing generally calc-alkaline characteristics are divided in basalt, andesite, latite-basaltand latite-andesite. The general distribution of their trace element contents (Cr, Ti, Zr, Sr, Y) and highV/Ni, low Ti/V values exhibit the characteristics of volcanic arcs rocks.It is concluded that the Sinop volcanics and the other volcanics of Upper Cretaceous-Eocene age inthe Pontids were generated by the subduction of the descending Anatolian-Tethys (Neo-Tethys) plate beneath the Pontids during the Upper Cretaceous-Eocene time.