We use the experimental setup and protocols described in Toutouni et al. (Effects of Temperature and Pressure on Interfacial Tensions of Fluid Mixtures. I. CO₂/n-Pentane Binary. J. Chem. Eng. Data, 2021, DOI 10.1021/acs.jced.0c01044) to examine the impacts of temperature and pressure on interfacial tensions (IFT) of binary hydrocarbon systems propane/n-pentane and propane/n-hexane. The pressure and temperature vary from 0.2 to 3.5 MPa and 323.15 to 403.15 K for the propane/n-pentane fluid system and from 0.18 to 3.5 MPa and 296.15 to 403.15 K for the propane/n-hexane fluid system. The results indicate that the IFT values of both fluid systems follow the same trends with changes in pressure and temperature. It is observed that when pressure increases isothermally, the IFT values decrease. Furthermore, when increasing temperature isobarically, the IFT values exhibit a decreasing trend at low pressures, but the trend reverses at higher pressures. The measured data also reveal that, at a given pressure and temperature, the IFT value of the propane/ n-pentane system is lower than that of the propane/n-hexane system. The difference between the two IFT values decreases as pressure increases isothermally.