Abstract:The Guo State cemetery is a large scale well preserved state cemetery with complete grade and orderly arrangement from the Western Zhou Dynasty to the Spring and Autumn Period. Fifty bronze samples from the Guo State cemetery were analyzed by metallographic microscope and SEM. The results show that the metallographic structure includes cast, heatness after casting, hot process after casting (local) and so on. The alloy includes lead-tin bronze and tin bronze. Lead isotope ratio measurements indicate common lead concentrated in a small range. It is speculated that the bronzes of different tombs have similar source of minerals.