A method for monitoring a spin imparted on an optical fiber in order to reduce Polarization Mode Dispersion (PMD) includes the steps of imparting a spin on a high-temperature optical fiber which is drawn from a preform, photographing a dispersion pattern peculiar to the spun optical fiber with a camera from scattered light naturally generated by the spin imparted on the optical fiber, and displaying the photographed dispersion pattern. The method enables monitoring of rate and period of the spin imparted on the optical fiber on the basis of the displayed dispersion pattern.