The ultrasonic velocity, density and viscosity in mixtures of sorbitan sesquioleate and poly(vinyl pyrrolidone) (PVP), poly(vinyl alcohol) (PVA) and poly(ethylene glycol) (PEG) in different concentration ranges are measured at different temperatures (303, 313 and 323 K). From the experimental data, other related acoustical parameters such as adiabatic compressibility (β), intermolecular free length (Lf), internal pressure (πi), Rao’s constant (Ra), relaxation time (τ), acoustical impedance (Za), absorption coefficient (α/f2), free volume (Vf), cohesive energy (CE) and solvation number (Sn) have been evaluated. In aqueous solutions, surfactant molecule starts to aggregate and form micelle in concentration called as critical micelle concentration (CMC). It is one of the most important physical parameters of the surfactants. These results were interpreted in terms of surfactantpolymer complex reactions. The combinations of surfactant with polymers improve the desired properties of the product and the formation of complex was confirmed by UV and FTIR studies.