This study was carried out to synthesis the zeolite using the bituminous coal fly ash emitted from power plant that occurs several environmental problems. In spite of fly ash has contained high content of $SiO_2$ and $Al_2O_3$, it disposed mainly landfill. If the effective methods to recover the $SiO_2$ and $Al_2O_3$ were developed, the fly ash could be utilized valuable raw materials. In this study, fly ash was used as raw material to synthesize the zeolite by pressurized hydrothermal reaction. Also, experimental parameters included temperature($70{sim}110^{circ}C$, and pressure($140{sim}200$ psi) of crystallization were investigated. The more crystallization pressure was increased, the more Zeolite 4A was synthesized at 70 and $90^{circ}C$. Zeolite 4A of metastable phase tend to be transformed into sodalite of stable phase at $110^{circ}C$.