To provide the growth degree measurement device of bean sprouts capable of accurately, measuring the growth degree of the bean sprouts inside a cultivation frame.

Inside the cultivation frame 1, sprinkling is received from a tray 2 at the upper part and the bean sprouts S are raised. The layer height measurement device 4 of the bean sprouts is arranged between the cultivation frame 1 and the tray 2 and the layer height measurement device 4 is provided with an arm 6 rotatable around a shaft 7 and an ultrasonic wave measurement device 5 attached to the arm 6. By recognizing the surface position of the bean sprouts S raised inside the cultivation frame 1 by the ultrasonic wave measurement device 5, the layer height of the bean sprouts cultivated inside the cultivation frame 1 is measured. The layer height measurement device 4 prevents the ultrasonic wave measurement device 5 from being wetted by sprinkling performed from the tray 2 to the cultivation frame 1 by rotating the 6 around the shaft 7 and detaching it from the lower part of the tray 2.