Abstract. Acoustic response of the solutions of potassium thiocyanate in water and 2-propanol+water mixtures have been investigated at 298.15, 303.15, 308.15 and 313.15 K. From the measured ultrasonic velocities and density data, acoustic parameters like adiabatic compressibility (β_ad), intermolecular free length (L_f), specific acoustic impedance (Z), relative association (R_A), solvation number (S_n), apparent molar compressibility (Φ_k) and molar volume (Φ_v) were calculated. Ultrasonic velocity is found to be maximum for potassium thiocyanate in 2-propanol+water mixture at x_2pr (mole fraction of 2-propanol) = 0.0257 indicating strong solvent-solvent interaction. Intermolecular free length and adiabatic compressibilities are lowest for the above composition. Solvation number of K⁺ is found to be 4±2. Gucker and Masson’s relations have been verified. The results obtained from the study were used to interpret ion-ion, ion-solvent and solvent-solvent interactions.