An investigation of a premixed methane-air flame was conducted with a slit burner between two parallel walls to examine the effects of wall material and temperature on flame quenching. Three different materials (i.e., zirconia ceramics, stainless steel 304, and Si) were tested at wall temperatures of 100-700 degrees C. The quenching distances for the three wall materials at the same temperature decrease in the order stainless steel 304Sizirconia ceramics. For all materials, the quenching distance shortens with increasing wall temperature. To clarify the differences among the materials, the surface structure and composition of the raw and used walls were characterized by X-ray diffraction and X-ray photoelectron spectroscopy. The results show that the percentages of chemisorbed oxygen on the surfaces decrease in the order zirconia ceramicsSistainless steel 304a behavior that can be correlated with the order of quenching distances of the three wall materials, which moves from small to large. In short, the higher the percentage of chemisorbed oxygen, the shorter the quenching distances.