Understanding the thermal properties of methane hydrate (MH)-bearing sediments is important to develop future energy resources. Thus, in this study, we measured the thermal properties of synthetic hydrate-bearing sediment samples comprising sand, water, methane, and MH using the hot-disk transient plane source technique. The melting heat of MH possibly affects the measurements; thus, the experiments were performed at supercooled conditions during MH formation in the sediment pores. The results show that thermal conductivity and diffusivity of the samples slightly increased as hydrate saturation increased from 0 to 0.3. We also performed thermal conductivity calculations using simple thermophysical models. The distribution model (geometric mean model) shows a relatively good agreement with the experimental data; however, it underestimates the thermal conductivity of the four-component sample. Thus, better prediction models are required to accurately determine the thermal properties of four-component systems.