In this work we present apparent molar volume ( Φ v), adiabatic compressibility ( Φ k) and sound velocity number [ U] of sodium dodecyl sulfate (SDS), sodium n-nonyl sulfate (SNS), sodium dodecyl benzene sulfonate (SDBS), cetyl trimethyl ammonium bromide (CTAB), and di (dodecyl dimethyl ammonium bromide) (12-2-12) in aqueous solution of β-lactoglobulin (βLG) between 10 and 36 °C at an interval of 2 °C. The temperature dependence of Φ v value of these surfactants is found to be completely consistent with temperature over the entire concentration range; two minima are seen to occur at 22 and 32 °C. The sharpness of the minima decreases with the increase in surfactant concentration. However, no such pattern is observed with Φ k value. Corresponding experiment with βLG (i.e., in absence of surfactant) shows two maximum at the same temperatures as does the minima in Φ v value of surfactants. [ U] and Φ k are found to contrast in their behaviour with regards to the effect of temperature and surfactant concentration. However, this is suggested to provide a consistent view as regards to the surfactant binding to protein. We fail to observe such a complex temperature dependence of Φ v value in the presence of 2-mercaptoethanol (a protein denaturant). Assuming complete denaturation of βLG, the surfactant binding to βLG is believed to be diversified into electrostatic and hydrophobic interactions.