Objective To explore the relationship between sleep time and Chinese medicine constitutional type.Methods Based on the database of physical examination of 1114 healthy subjects

information on gender

age

marital status

smoking

alcohol consumption

educational background

exercise

average daily sleep time

and chronic medical history of the subjects was collected. Investigation of constitution were scored by using Chinese medicine constitution scale. With the constitutional type score as the T axis

and the hours of sleep as the X axis

a scatter diagram was drawn. The relationship between the hours of sleep and Chinese medicine constitutional type was explored using multiple linear regression analysis method. Results Totally 1065 cases were included into analysis. Scatter diagram and the fitting regression line of sleep time and Chinese medicine constitutional type showed that sleep time was significantly positively correlated with the Balanced constitution（ r = 0. 123

P = 0. 001）. Eight kinds of biased constitution were negatively correlated with sleep time

with Qi-deficiency constitution（ r = 0. 065

P = 0. 029）

Yangdeficiency constitution（ r = 0. 081

P = 0. 007）

Yin-deficiency constitution（ r = 0. 058

P = 0. 04）

phlegm-dampness constitution（ r =- 0. 062

P = 0. 038）

and Qi-stagnation constitution（ r = 0. 079

P = 0. 008）. After adjusting factors like gender

age

marital status

educational background

exercise

smoking

alcohol consumption and chronic disease

the results of multiple linear regression were similar to the original results. Conclusion The sleep time seems to be correlated with Chinese medicine constitutional type. Adequate sleep time should be guaranteed to prevent the formation of biased constitution.