The speeds of sound in 1,2- and 1,3-butanediol have been measured in the temperature range from (293 to 318) K at pressures up to 101 MPa by the pulse-echo-overlap method. The densities of both the butanediol isomers have been measured in the temperature range from (288.15 to 363.15) K under atmospheric pressure with a vibrating tube densimeter. From the experimental results the densities, isobaric heat capacities, isobaric coefficients of thermal expansion, isentropic and isothermal compressibilities, as well as the internal pressure as function of temperature and pressure have been calculated. The effects of pressure and temperature are discussed.