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The aim of this study was to obtain an index for leavened solid foods that even an elderly person could chew and swallow. Physicochemical properties of the solid food prepared with polysaccharides (replaced 0.5 or 3.0% to soft wheat flour) and its artificial bolus were evaluated. The solid food and its artificial bolus had desirable physicochemical properties formulated with glucomannan, gum arabic or agar. However, the crumb softness of solid food could not be maintained by formulation of polysaccharide. Therefore, addition of emulsifier (formulated 1.0% for soft wheat flour) was considered. The solid foods prepared with glyceryl monostearate (GMS)+gum arabic (A) and sucrose esters of stearic acid with HLB of 3 (SES3)+glucomannan (G) were selected as the samples with different chewing and swallowing characteristics. The flow velocity of bolus was measured by an ultrasonic imaging device. The velocity was fast in order of water (0.48 m/s), yogurt (0.31 m/s), and solid foods (0.19 – 0.28 m/s). GMS+A sample with high softness and low saliva absorption, and SES3+G sample with low softness and high saliva absorption showed almost the same flow velocity of yogurt. Healthy person can form a bolus with desirable flow velocity for swallowing from the sample with low softness and high saliva absorption. Therefore, the sample with high softness and low saliva absorption was deduced to be suitable for an elderly person. Then artificial bolus which changed water contents was prepared, and mechanical properties (dynamic viscoelasticity, hardness, and friction coefficient) were measured. The property value decreased with the increase of the water content of the artificial bolus. From these results, it was speculated that bolus which had low storage modulus (< 0.5 Pa, 9.42 rad/s) and sufficiently coated layer with saliva might be desirable for deglutition easiness.