砄bjective:To analyse the effects of age on the color of natural tooth crown. Methods: The color of 1 944 health anterior teeth of 162 chinese people aged 20 to 73 years old was measured with a fiber optic spectrophotometry system. CIE 1976 L *a *b * and CIE 1931XYZ were applied to analyse the color mesurements. Results:The results showed that in three section of teeth(incisor, midlle, cervical) the values of L * and a *were negativly correlated to aging, that of b * was positively just at cervical and midlle sites. The value of b * was not related to age at incisal site of teeth. Conclusion: The values of L * and a * are related to age negatively.