The attenuation, α, of ultrasonic longitudinal waves propagating in the (111) direction in monocrystalline Ge, GaSb, and InSb [1] is investigated. The measurements were made in the frequency range 100 to 350 MHz and at temperatures of 7 to 300 °K using the pulseecho technique. At temperatures below 20 °K, the attenuation is independent of temperature for a given material, but depends on frequency. At temperatures above 20 °K, it is found that for the three materials the change of the ultrasonic attenuation with respect to the residual attenuation α0 depends only on the lattice scattering. The ultrasonic low‐energy phonons and the transversal thermal phonons are only involved in the three‐phono, process of scattering. The temperature dependence is fitted using the theory of Maris.