Sealing glasses are necessary materials for the scaling process in electronic applications. Our goal is to develop lead-free glasses with a low melting temperature (less than 600 degrees C) and good chemical durability for sealing. In this study, Li2B4O7, ZnO, KPO3, Nb2O5, and Al2O3 were used to prepare lead-free glasses. Glass transition temperature, softening temperature, thermal expansion coefficient, and water resistance were measured in detail in ternary (Li2B4O7-ZnO KPO3) and quaternary (Li2B4O7-ZnO-KPO3-Nb2O5 or Li2B4O7-ZnO-KPO3 Al2O3) systems. The lead-free glass with 24 wt% Li2B4O7-6 wt% ZnO-70 wt% KPO3 had a high sealing property (sealing temperature: 450 degrees C), an amorphous structure, and a low melting point. However, it had a low water resistance (weight loss: 30%) and a high thermal expansion coefficient (14.5 x 10(-6) /K). On the other hand, 21.6 wt% Li2B4O7-5.4 wt% ZnO-63 wt% KPO3-10 wt% Nb2O5 glass had a high water resistance (weight loss: 1.6%), a low thermal expansion coefficient (12.7 x 10(-6)/K), a high sealing property (sealing temperature: 480 degrees C), an amorphous structure, and a low glass transition temperature. The prepared lead-free glass exhibited a high performance as a substitute for the commercially available lead glass.