Abstract: The content of 16 kinds of precedence-controlled Polycyclic Aromatic Hydrocarbons (PAHs) of surficial sediment in Laizhou Bay is investigated. The total PAHs content is between 239.25 10-9 to 697.06 10-9, with an average of 499.9 10-9. Flu and Phe are the highest content which is 191.04 10-9 and 167.60 10-9 respectively. The PAHs mainly come from the burning of wood, coal and fossil oil and the oil spill according to the principal component analysis. The ecological risk assessment is analyzed using the method of Mean effects range median-Quotient. The results show that the ecological risk is relatively low in Laizhou Bay. The total content and ecological risk of PAHs in surficial sediment of Laizhou Bay are rising rapidly in recent years.