In this paper, a flow calorimeter was developed to measure the isobaric specific heat capacity of ethyl fluoride (HFC-161) in both liquid and vapor phase. 161 data of isobaric heat capacity of HFC-161 were obtained in liquid phase at temperatures from 303.51 K to 383.71 K and pressures up to 12.0 MPa 38 data were acquired in vapor state in the temperature range of 315.43 K-365.40 K and pressures from 1.0 MPa to 3.0 MPa. The uncertainties of the heat capacity for HFC-161 were estimated to be less than 1.0% in liquid phase and 1.5% in vapor phase, respectively. The equations of state based on specifying the Helmholtz free energy were employed to calculate the isobaric heat capacity for HFC-161. In addition, the experimental values of heat capacity in liquid phase were also compared with the literature data. (C) 2016 Elsevier B.V. All rights reserved.