Longitudinal and transverse wave velocities, five kinds of elastic parameters (Young’s, shear and bulk moduli, Lame parameter, Poisson’s ratio), Debye temperature, and dilational and shear internal frictions for fused quartz were simultaneously measured over the temperature range from 73 to 400 K, using the ultrasonic pulse wave with frequency of 7.7 MHz. Large increase in Young’s and bulk moduli and small increase in shear modulus and Lame parameter suggest enhancement of rigidity for K-I mode on heating. This would be explained by quasi-crystallization which is associated with a lateral motion of oxygen atoms and the resulting relief of macroscopic strains. The 99 and 137 K peaks and 360 K one in shear friction are probably related to dielectric loss peaks arising from Al3+-Na+ and Al3+-K+ substitutional-interstitial paired defects and to beta(1)/beta(2)-tridymridymite phase transition, respectively.