In this work, ultrasonic velocity measurements in the compressed liquid phase of three branched alkanes (2-methylpentane, 2,3-dimethylpentane, and 2,2,4-trimethylpentane) from (293.15 to 373.15) K and for pressures ranging up to 150 MPa are presented. These results were used to estimate various thermophysical properties such as density and isentropic or isothermal compressibilities in the same range of pressure and temperature.