The invention relates to a self-propelled leaf vegetable harvester, and belongs to the technical field of agricultural harvesters. The harvester comprises a door-shaped frame crossing a caterpillar base plate and a driving system located at one side of the caterpillar base plate, a copying conveying device located on a header frame is installed on the caterpillar base plate, the front end of the copying conveying device is located on the lower portion of the caterpillar base plate, and the rear end of the copying conveying device extends to penetrate through the door-shaped frame to be located above the back of the caterpillar base plate; the copying conveying device is composed of a vertically surrounded lower lifting conveying belt and an upper waveform conveying belt matched with the lower lifting conveying belt to form a spaced copying space, the entering end of the lifting conveying belt lags behind the input end of the waveform conveying belt, and a disc cutting device is installed below the portion between the input end of the waveform conveying belt and the entering end of the lifting conveying belt. Accordingly, leaf vegetables can be protected through the copying space of the waveform conveying belt, leaf vegetable breakage and cutting loss are effectively avoided, feeding in a line alignment mode is not needed, and the harvesting quality is guaranteed while efficient harvesting is conducted.