Glasses in K2O-Na2O-MgO-Al2O3-SiO2-F system were crystallized to prepare machinable glass-ceramics. The optimum nucleating and crystal growing temperatures were approximately $700^{circ}C$ and 1060~112$0^{circ}C$, respectively for the samples investigated. Crystalline phases of sellaite, norbergite, and fluorphlogopite appeared progressively as heat-treatment temperature was increased. Surface roughness of the crystallized specimens after the machining was similar to that of metal aluminum (2.18 ${mu}{ extrm}{m}$). Thermal expansion coefficient, Vickers hardness and dielectric constants of the fluorphlogopite glass-ceramics prepared were 7.37~10.21 ($ imes$10-6/$^{circ}C$), 302~456kgf/$ extrm{mm}^2$ and 5.97~16 respectively.