In this study, we present new experimental heat capacity data of solid and liquid phase of CsF covering the temperature range from 5K to 1400K. The low temperature data were obtained by adiabatic calorimetry and compared with the theoretical heat capacity computed from ab initio harmonic crystal approximation. The absolute entropy at T=298.15K determined based on the presented results is 93.60J·K-1·mol-1. The high temperature heat capacity was measured using a drop calorimeter and the data for the solid phase revealed significant excess properties. The data for the liquid phase were correlated with the molecular dynamic simulation obtaining a good agreement. The recommended molar heat capacity of the CsF solid phase is:Cp,m(J·K-1·mol-1)=24.291+6.4607·10-2·(T/K)+589981·(T/K)-2J·K-1·mol-1and the one of the liquid phase was determined as:Cp,m=70.56J·K-1·mol-1.From the calorimetric results the enthalpy of fusion of CsF was determined as:△fusH=22.1±2.0kJ·mol-1.