A water content evaluation apparatus which evaluates water content of a part of a plant is provided. A water content at each of irradiation positions of the part of the plant is calculated based on a first reflection light of a laser reference beam, having a first wavelength that is not absorbed by water, that is reflected at all the irradiation positions of the plant and a second reflection light of a laser measuring beam, having a second wavelength that is absorbed by water, that is reflected at all the irradiation positions of the plant. Irradiation positions of the plant in which the water content is equal to or larger than at least one predetermined threshold level are displayed, in at least one corresponding predetermined color.