Abstract: Hydrocarbon gas has features of higher volatile，big migration distance，deep reflecting，and anomalies forming around ore bodies.Therefore，the hydrocarbon measurement method has been used to forecast the deep ore-prospecting in Longkou lead-zinc deposit.According to analysis on the content features of hydrocarbon components in different types of rock and the correspondence between hydrocarbon anomalies and the lead-inc ore in space，with the combination with geological and structural features，the deep mineralization potential in the region is evaluated and some valuable ore prospecting sections are outlined.

Key words: Hydrocarbon gas, Deep ore prospecting forecast, Longkou lead-zinc deposit