Abstract: Based on a preliminary analysis of the Quaternary mammalian fossils unearthed near North ErshiJiazi Town in Jianping County， of Liaoning Province， it was found that these fossiles are the antlers of megaloceros， developed from the warm humid steppe ecosystem during the Cenozoic midPleistocene. By a contrast study of regional stratigraphy and other fossils， these fossils with strong siliconization were formed in the early Pleistocene. The antler fossils were buried in the loess soil， a product of the dry and cold weather conditions， so the studied area had been warm and humid， and became dry and cold hereafter. It might be concluded that the mammals were affected more by climate changes and finally died out.

Key words: west of Liaoning province, megaloceros, fossil, Quaternary, contrast