Isobaric heat capacities of R1234ze(E) were investigated by using a modified flow calorimeter covering a temperature range from 313 to 393 K and pressures up to 10 MPa. The uncertainties in measurement of the heat capacity were estimated to be less than 0.01 at temperatures below 373 K, rising to 0.02 in the near critical region (373 and 393 K). An empirical equation was developed for correlation on the basis of the experimental data. In addition, a comparison was made between the present data and literature values.