The main objective in saw construction development is to ensure as fast as possible rotation velocity of a saw and to obtain straight and narrow kerf. During the operation circular saw is affected by various factors of load - forces of resistance to cutting, uneven incandescence of the saw in the direction of radius and etc. It was determined, that in many cases saw performance ability is related to its dynamic stability. In this monograph are analysed the problems of the dynamic stability of wood circular saws. There is presented the methodology of evaluation of circular saws viscoelastic properties and required equipment. For evaluation of saw properties the theoretical calculations of circular isotropic plate oscillations is applied. Quasiisotropic (simple construction) and anisotropic (special construction) saws are studied. The amplitude-frequency characteristics, modes and the distribution of viscoelastic properties in the saw plane are presented. Also the influence of peripheral part deformation, tightening moment, operational temperature, sawing wood is evaluated. Comparable data of different construction saws are given.