Abstract: Maturation index and maturation of Liquidambar formosana seeds were studied based on moisture content and specific gravity of fruiting heads, crude fat content of seeds. The results showed that crude fat content of seeds is the accurate quantitative indication of Liquidambar formosana seed maturation, moisture content in fruiting heads also predicts the seed maturation, fruiting heads specific gravity and colour give no promise as a maturity index and Liquidambar formosana seeds mature in early October in Nanjing.