Four kinds of rice with different ratios of amylose and amylopectin were studied to examine the relationships between the physical properties of the cooked rice samples and their ease of eating, physical properties, sensory evaluation, and electromyography of the masseter muscles. The physical properties were measured for the mass of cooked rice by two methods:measurement with the sample stuffed into a stainless-steel ring, and measurement with the sample released from the ring. It was assumed that the cooked rice bolus would be dispersed inside the mouth during eating. The physical properties were also measured for a single grain of cooked rice. The results indicated that the hardness value obtained from measurement with the sample stuffed into the ring was useful for estimating the hardness of the sample inside the mouth, whereas the cohesiveness value obtained from measurement with the sample released from the ring was useful for estimating the dispersion of the sample inside the mouth. Assuming the dispersion characteristics of the bolus inside the mouth, these results will elucidate the ease of eating of cooked rice.