The ultrasonic properties like ultrasonic sound velocity in the hexagonal structured intermetallic nanostructure SrGa2 compound has been studied along unique axis at roomtemperature. The second- and third order elastic constants (SOEC&TOEC) have been calculated for this compound using LennardÂJones potential. The velocity VL and VS2 increaseswith the angle fromunique axis,whileVS1 andVDhavemaximawith 450with unique axis of the crystal. The inconsistent behaviour of angle dependent velocities is associated to the action of second order elastic constants. Debye average sound velocities of SrGa2 are increasing with the angle and has maximum at 450 with unique axis at room temperature. Hence when a sound wave travels at 450 with unique axis of SrGa2compound, then the average sound velocity is found to be maximum. The mechanical properties of SrGa2are better than other intermetallic compounds BaGa2 and CaGa2 at room temperature, because it has high ultrasonic velocity and low ultrasonic attenuation. The comparison of calculated ultrasonic parameters with available theoretical/experimental physical parameters gives information about classification of this compound.