A toroidal-type continuously variable transmission is obtainable having excellent durability without generating vibration. Given each inner diameter of the power rollers as d.sub.i, the outer diameter thereof as d.sub.o, and the diameter of each pitch circle of the plural balls which constitutes the thrust ball bearings as d.sub.p, an expression of 3 d.sub.o.sup.2 /(d.sub.i ·d.sub.p) 5 is satisfied. As a result, the tensile stress can be suppressed to less than its fatigue limit. Thus any damage, such as cracks, due to repeated tensile stresses in the inner diametral portion of the power rollers are reduced. Also, the maximum contact pressure is suppressed to less than its critical contact pressure in order to prevent any indentations from being formed on the surface of the raceways arranged for the power rollers.
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