The invention discloses a fire prevention and extinguishing integrated system and method adopting liquid CO2 refrigeration in a mine. A CO2 evaporator is mounted in a zone air inlet roadway, thus, high-pressure liquid CO2 is gasified and absorbs heat in the evaporator, and the CO2 evaporator is cooled and absorbs heat in the roadway, so that an underground mining face is cooled; and after the liquid CO2 is gasified and absorbs a large amount of heat in the evaporator, the CO2 enters a gaseous CO2 conveying pipeline, the low-pressure gaseous CO2 is compressed into the high-pressure liquid CO2 through a CO2 compressor, the high-pressure liquid CO2 is conveyed to the downhole through a high-pressure liquid CO2 conveying pipeline, and thus CO2 recycling is achieved. After the liquid CO2 is gasified, absorbs heat in the CO2 evaporator and is cooled, the gaseous CO2 is formed, part of the CO2 is injected into a goaf (oxidizing zone) through a first CO2 releasing pipeline, thus oxidative spontaneous combustion of coal in the goaf is restrained, and the certain cooling effect is achieved on the goaf.