The invention discloses an economical thermal power plant ammonia-containing wastewater treatment system and an economical thermal power plant ammonia-containing wastewater treatment method. The economical thermal power plant ammonia-containing wastewater treatment system comprises a regulation basin, a deaminizating agent storage tank, a caustic soda liquid storage tank, an ammonia-removing column, an acid storage tank, a clean water basin, a steam-water separation device, a draught fan, a high-salinity wastewater treatment system and a centrifugal fan; the outlet of the regulation basin, the outlet of the deaminizating agent storage tank and the outlet of the caustic soda liquid storage tank communicate with the inlet of the top of the ammonia-removing column, both the outlet of a slurry basin of the bottom of the ammonia-removing column and the outlet of the acid storage tank communicate with the inlet of the clean water basin, the air outlet of the top of the ammonia-removing column communicates with the inlet of the steam-water separation device, the liquid outlet of the steam-water separation device communicates with the inlet of the regulation basin, the gas outlet of the steam-water separation device communicates with an external device through the draught fan, the outlet of the clean water basin communicates with the inlet of the high-salinity wastewater treatment system, and the air outlet of the centrifugal fan communicates with the air inlet of the slurry basin of the bottom of the ammonia-removing column. The invention can effectively treat ammonia area wastewater and fine treatment regenerated high-salinity wastewater, and moreover, the cost is low.