Fly ash vitrification technology is an effective method for handling by-products from waste incineration. However, traditional refractory materials such as electric fused zirconia-corundum refractory bricks (AZS) are susceptible to erosion by calcium oxide (CaO) and chloride ions in fly ash under high-temperature conditions, which affected the service life and efficiency of melting furnaces. This study investigated the application and advantages of electric fused cast Z80 bricks (with a mass fraction of ZrO₂ of approximately 80%) in fly ash vitrification electric melting furnaces. Experimental results showed that Z80 bricks exhibited excellent erosion resistance, thermal shock stability, and low bubble precipitation rates. After continuous operation at 1 360~1 400 ℃ for three months, the average erosion rate of Z80 bricks was only 0.6 mm/month, significantly lower than the 1.6 mm/month observed for AZS41# bricks. Furthermore, composite refractory structures combining Z80 and AZS bricks as refractory materials enhance overall material performance and cost-effectiveness. These finding provided a scientific basis for optimizing furnace design and promoted the wider adoption of fly ash vitrification technology.