High entropy alloys (HEAs) are a class of materials promising for plasma-facing applications in fusion energy devices. Among them, Tungsten (W-) based HEAs have been considered as leading candidates due to remarkable properties including superior mechanical properties, a superior melting point (above 2873 K), enhanced radiation resistance to heavy ion irradiation, and negligible radiation hardening compared to pure W. However, there is a lack of understanding of how mechanical and thermodynamics properties of W-based HEAs are affected by temperature. In this work, we present a study on the temperature-dependent thermal properties of W-based HEAs. The first-principles density-functional-theory (DFT) calculations combined with quasi-harmonic approximation (QHA) theory is used to investigate electronic, structural, and thermal properties of HEAs in different chemical compositions as a function of temperature. Our work advances understanding of structural-mechanical-thermal relations in HEAs, thus providing insights on inverse design of candidate HEAs in fusion energy devices.