High-temperature erosion caused by calcium magnesium aluminum silicate (CMAS) poses a significant challenge to the advancement of thermal barrier coatings (TBCs). In this investigation, four multi-component A2B2O7 type oxide TBC materials, namely Eu2(Y0.2Ce0.2Zr0.2Hf0.2Ta0.2)2O7, Eu2(Y0.2Yb0.2Ce0.2Nb0.2Ta0.2)2O7, Eu2(Y0.2Yb0.2Zr0.2Nb0.2Ta0.2)2O7, and Eu2(Y0.2Yb0.2Hf0.2Nb0.2Ta0.2)2O7, were synthesized using the solid-state method. We investigated the corrosion behavior of molten CMAS on the samples at 1300 °C for durations of 1 h, 20 h, and 50 h. The resulting corrosion products consist of apatite and cubic fluorite structures. Our analysis reveals that as the ionic radius of RE3+ increases, the stability of the apatite structure improves. Furthermore, molten CMAS exhibits varied wetting behaviors on different substrates at the same temperature. A higher contact angle suggests that the CMAS melt will encounter difficulty in diffusing and penetrating the substrate surface. This research will contribute to the development of TBC materials with enhanced resistance to CMAS corrosion.