The invention provides a hydraulic tobacco leaf cutting machine. The hydraulic tobacco leaf cutting machine comprises a rack and a conveyor belt arranged on the rack, wherein a cigarette end stable pressing mechanism is arranged above the conveyor belt. The hydraulic tobacco leaf cutting machine is characterized in that a water cutter oriented fixing mechanism is arranged on the cigarette end stable pressing mechanism; a water cutter head is arranged on the water cutter oriented fixing mechanism; the upper end of the water cutter head is connected with a pressure water pipe; and the lower side of the water cutter head is joined with a water receiving pipe, but is not connected with the water receiving pipe. A water cutter which is not blunt all the time and is sharp and sanitary is used for cutting tobacco leaves, so that heavy working amount of maintaining and replacing blades is greatly reduced; the labor intensity of workers and the maintenance cost are reduced; and more importantly, the cutting length of different tobacco leaf sections are properly adjusted according to the length of the tobacco leaves and process requirements. Furthermore, pure water is used for cutting, so that the tobacco leaves are not mixed with any harmful substance; and when leaf threshing requirements are met, reliable technical support and guarantees are provided for finally obtaining the high-quality tobacco leaves.