The density and isobaric heat capacity of the binary system {alpha-pinene (4,7,7-trimethylbicyclo[3.1.1]hept-3-ene (1), CAS Number 7785-26-4) + beta-pinene (6,6-dimethyl-2-methylene-bicyclo[3.1.1]heptane (2), CAS Number 127-91-3)} has been measured for eleven different compositions. The density was determined at five pressures from (20 MPa to 40 MPa) and temperatures from (283.15 K to 358.15 K) and the isobaric heat capacity at atmospheric pressure and temperatures from (313.15 K to 418.15 K). Density was measured with an experimental uncertainty estimated to be +/- 0.5 kg.m(-3). The isothermal compressibility and isobaric thermal expansion were derived from the experimental density data. The isobaric heat capacity was determined with a DSC calorimeter being the experimental uncertainty lower than 1.5%. Isobaric heat capacity behaviour was as expected for both pure compounds and for mixtures. Two different equations of state, conventional SAFT and PC-SAFT, were applied to calculate the densities of the mixture, being the best predictions achieved with PC-SAFT equation. (C) 2012 Elsevier Ltd. All rights reserved.