K2O-Al2O3-SiO2 glass-ceramics were prepared by sintering method. The effects of glass powders with different particle size distribution on the crystallization and microstructure of K2O-Al2O3-SiO2 glass-ceramics were studied, so as to optimize the particle size of K2O-Al2O3-SiO2 glass-ceramics. The results show that the crystallization temperature of glass-ceramics decreases from 913.9 oC to 869.9 oC when the median particle size of glass powder decreases from 38.09 μm to 1.80 μm. Crystallization activation energy also decreased from 320.5 kJ/mol to 234.7 kJ/mol. The crystallized phase of the glass-ceramics are both leucite. When the median particle size of the glass powder is 6.30 μm, the microstructure of the glass-ceramics is more uniform. The glass-ceramics has a density of 2.45 g·cm-3, a flexural strength of 74.93 MPa, and a thermal expansion coefficient of 14.32×10-6 K-1.