To provide a measurement method for simply, easily and quickly measuring the content of chemical components in tea leaves, including raw tea leaves, dried tea leaves and finished tea leaves.

The absorbances of the target tea leaves with chemical components, having known concentrations, are measured using near-infrared spectrophotometer. The concentrations of the chemical components are calculated from the absorbances of the tea leaves with the chemical components having unknown concentrations, based on the information of the correlation between the absorbance and the quantity of the chemical components of the target tea leaves.