The present work is focused on the determination of elastic, mechanical, ultrasonic and thermal properties of ScRu intermetallic under the variation of pressure 0–60 GPa and particle size 5–40 nm. Initially, the second order elastic constants (SOECs) have been computed under a potential model approach, in which interaction potential is defined by Coulomb and Born–Mayer potentials. Later on, the estimation of mechanical, ultrasonic and thermo-physical parameters has been performed using SOECs. The ultrasonic velocities are estimated in the same pressure/particle size range for wave propagation along 〈100〉 crystallographic direction. It is found that elastic constants, ultrasonic velocities, Debye average velocity, specific heat at constant volume, thermal energy density, thermal conductivity and melting point enhance with increase in pressure and decay in particle size in chosen intermetallic. The analysis of the obtained results reveals that the elastic, mechanical and thermal properties of ScRu intermetallic shall enhance effectively under pressure in comparison to decay in particle size.