A liquid-proof fabric stitcher and a stitching method therefor. The liquid-proof fabric stitcher comprises multiple liquid-proof fabric layer units stitched by means of a heat-sealing method, each of the liquid-proof fabric layer units comprises: at least one liquid-proof film layer (2), at least one thermoplastic non-woven fiber layer (1, 3), and a discontinuous bonding layer located between the at least one liquid-proof film layer (2) and the at least one thermoplastic non-woven fiber layer (1, 3). The heat-sealing temperature of the heat-sealing method is lower than or equal to the total melting temperature T4 of the liquid-proof film layer (2), but is higher than the maximum start melting temperature T3 of the thermoplastic non-woven fiber layer (1, 3). By means of adopting a multicomponent liquid-proof film layer (2) having two or more melting ranges, the range between the start melting temperature and the total melting temperature can be broadened, and the stitching process can be widened.
