The invention relates to a micro-drainage water purification machine.The water purification machine comprises an electrolysis unit, a reverse osmosis membrane treatment unit and a finished water tank.The electrolysis unit comprises paired electrodes and a source water tank.A first water-permeable diaphragm and a second water-permeable diaphragm are arranged between the negative electrodes and the positive electrodes of the first electrode pair and the second electrode pair respectively.A first window and a second window are formed in the opposite side walls of the source water tank respectively.The first window and the second window are covered with the first water-permeable diaphragm and the second water-permeable diaphragm respectively.The negative electrode and the positive electrode of the first electrode pair and the positive electrode and the negative electrode of the second electrode pair are arranged inside and outside the source water tank respectively.A water outlet of the source water tank is formed in a porous adsorption material inside the source water tank and is communicated with a water inlet of the reverse osmosis membrane treatment unit.A pure water outlet of the reverse osmosis membrane treatment unit is communicated with the finished water tank, and a concentrated water outlet of the reverse osmosis membrane treatment unit is communicated with the source water tank.According to the water purification machine, the purification effect on source water and the water outflow efficiency of pure water can be improved, only a trace amount of wastewater is drained, and therefore source water resources can be saved.