A water purification machine is disclosed. The water purification machine comprises a shell, a filtering system, a booster pump, a water inlet magnetic valve, a wastewater magnetic valve, and the like, wherein the filtering system, the booster pump, the water inlet magnetic valve, the wastewater magnetic valve, and the like are arranged in the shell. The water purification machine is characterized in that: the filtering system comprises a front polypropylene (PP) filter core, a composite filter core and back filter cores; the composite filter core comprises a filter shell; a filtering material of a coarse filtering system and a reverse osmosis (RO) membrane filtering material of a fine filtering system are sequentially sleeved and packaged in the filter shell from outside to inside; and a source water inlet, a concentrated water outlet and a pure water outlet which are communicated with corresponding connecting pipes are formed in the bottom of the filter shell. Various levels of filtering materials are integrated and packaged in the composite filter core, so that the cost of plastic parts and the space occupied by the filter core are largely reduced, connectors and polyethylene (PE) pipes which are used for connecting the filter cores are also not needed, and the material cost and the labor cost are reduced. In addition, internal connectors are reduced, so that the error of water leakage is largely reduced. The water purification machine is simple and reasonable in structural layout, small in occupied space, low in cost, simple in production process, reliable in sealing performance and convenient to maintain and replace.