In our previous study, we prepared four types of V₂O₅-H₂WO₄-KPO₃ glasses containing Sb₂O₃ (Sb₂O₃ content: 0, 1.3, 2.6 and 5.1 mol%) and examined their physical properties as a sealant. In this paper, we evaluate the physical properties of V₂O₅-H₂WO₄-KPO₃ glass containing 3.9 mol% Sb₂O₃. The glass had both optimum high water durability and optimum high fluidity, compared with the previous glasses containing 0, 1.3, 2.6 and 5.1 mol% Sb₂O₃ and a commercial lead-based glass. Addition of Zr₂(WO₄)(PO₄)₂, a low thermal expansion ceramic filler, to the V₂O₅-H₂WO₄-KPO₃-3.9 mol% Sb₂O₃ glass resulted in increased bonding strength of the glass, and the strength was very close to that of the commercial lead-based glass. These results show that the V₂O₅-H₂WO₄-KPO₃-3.9 mol% Sb₂O₃ glass is promising as an alternative to lead-based glass sealant. Additionally, glass structures of V₂O₅-H₂WO₄-KPO₃-Sb₂O₃ glasses were examined to determine the possible mechanism for improved water durability by the incorporation of Sb₂O₃.