This paper contains the measurements of isothermal VLE data for the binary system {trifluoroiodomethane (R13I1) + isobutane (R600a)} at four temperatures from (263.15 to 293.15) K. The measurements are performed by means of an apparatus based on the static-analytic method. The combined standard uncertainties of the measured results are +/- 5 mK for temperature, +/- 0.00025 MPa for pressure, +/- 0.005 for mole fraction of the liquid and vapour composition. The VLE data are correlated with the Peng-Robinson equation of state and the Huron-Vidal mixing rules involving the NRTL activity coefficient model. The model is successfully verified to be suitable for calculating the VLE data of the system measured. The experimental results show that {trifluoroiodomethane (R13I1) + isobutane (R600a)} is a zeotropic system. (C) 2012 Elsevier Ltd. All rights reserved.