The isobaric specific heat capacity of kerosene RP-3 was experimentally measured using a vacuum flow-calorimeter in the near critical and supercritical regions. During the experiments, the qualitative temperature changed from (292.1 to 823.9) K, and the operation pressure changed from (2.40 to 5.98) MPa. The operation pressure, fuel inlet and outlet bulk temperatures, mass flow rate, and heat power were measured using a pressure gauge. transducer, K-type sheathed thermocouples, a Coriolis force flow meter, and current and voltage meters, respectively. The estimated uncertainty of the measurement was lower than 2.11 %. The expanded accuracy of the measured method for the low temperature region was verified by the water at the pressure of 3.01 MPa; the high temperature region was verified by comparing the temperatures calculated from C-p integrating enthalpy with the temperatures measured in the experiments.