The densities, ρ and speeds of sound, u of D(−)-ribose in aqueous solutions of ammonium based protic ionic liquid i.e. 3-hydroxypropylammonium acetate (3HPAAc) have been measured at temperatures (298.15 to 318.15) K and at atmospheric pressure. These experimental data were used to calculate apparent molar volumes, V2,φ, apparent molar isentropic compressibilities, Ks,2,φ, infinite dilution partial molar volumes, V2°, and partial molar isentropic compressibilities, Ks,2° and the corresponding volumes of transfer (ΔtV2° and ΔtKs,2°). Both ΔtV2° and ΔtKs,2° values were found to be positive, which increase with cosolute (3HPAAc) concentration and temperature, which indicate the presence of hydrophilic-ionic types of interactions between D(−)-ribose (Rib) and ions of 3HPAAc. Various derived parameters such as expansion coefficients, hydration numbers, pair and triplet interaction coefficients for Rib in aqueous 3HPAAc solutions has also been evaluated and discussed.