The unfired Al 2 O 3 –C slide plates have the advantages of energy saving, environment friendly, efficiency and relatively low-cost. However, the decomposition and oxidation of the phenol-formaldehyde (PF) resin at elevated temperatures deteriorate the properties and decrease service life of the unfired slide plates. In order to improve the property of resin, the doped PF resin is prepared by incorporating Al(H 2 PO 4 ) 3 , Zn and B 4 C powders. The effects of the doped resin on medium-high temperature properties and microstructure of the unfired slide plate materials have been investigated. The results show that Zn and B 4 C doped resin contributes to notable increasing the density and strength properties at medium temperature, because Zn and B 4 C easily oxide and thus protect resin from oxidation, leading to form a dense structure. Zn and B 4 C doped resin can significantly improve hot modulus of rupture of the materials at 1400 °C, which is due to Zn and B 4 C react with oxidative gases leading to increase in concentration of C(g), CO and N 2 , Al and Si would react with C(g), CO(g) and N 2 (g) to form AlN and SiC whiskers creating strengthening effect. Specimens with Zn and B 4 C doped resin addition have good oxidation resistance at 1500 °C, because Zn and B 4 C in the surface of the material react with O 2 to form ZnAl 2 O 4 or mullite containing dense glass film, which would retard O 2 diffusion into the inner of the specimens.