This work investigated saturated vapor pressure and isothermal vapor-liquid equilibrium (VLE) for 1,1,1,2-Tetrafluoroethane (HFC-134a) + 3,3,3-trifluoropropene (HFO-1243zf) binary system. The saturated vapor pressures of HFC-134a and HFO-1243zf ranging from (273.17-353.13) K, and VLE data at four temperatures (283.15, 293.15, 313.15, 323.14) K for the HFC-134a + HFO-1243zf system were measured by a static-analytical apparatus. The vapor pressure data of HFO-1243zf were regressed by a Wagner type equation and compared with existing literature data. The experimental VLE data of HFC-134a + HFO-1243zf system were correlated by Peng-Robinson (PR) equation of state (EOS) combined with van der Waals (vdW) mixing rules. The binary interaction parameters were obtained, and correlation deviation was acceptable. Azeotropic behavior can be found for the HFC-134a + HFO-1243zf system at measured temperatures. Our work provides fundamental thermodynamic properties of new mixed refrigerants which are crucial to evaluate their cycle performance and optimize the design of refrigeration system. (C) 2019 Elsevier B.V. All rights reserved.