The invention relates to a production process for black nylon stretch yarns. The production process comprises the steps of proportional mixing of nylon chips and black master batches in a master batch mixer, melting in a screw extruder, metering with a metering pump, spinning with a spinning component, cross air blowing cooling, bundling and oiling, packaging, balancing, and texturing, wherein 4 to 10 weight percent of black master batches are added; the temperature of the extruder is 250 to 280 DEG C; the temperature of a spinning box body is 250 to 270 DEG C. The production process has the beneficial effects that differences between the relative viscosity, melting point and the like of the black master batches and those of the spinning chips are little, so that a melt is substantially stable, the black master batches can be uniformly mixed with the melt, the problems of floating yarns, yarn waste, looping yarns and the like during spinning are reduced, and produced black nylon stretch yarn products are deep black; the spinning process is greatly different from the conventional process, and the temperature of each area of the extruder is set to be 250 to 280 DEG C, so that carbon black in the black master batches can be uniformly dispersed in the melt, the melt is endowed with higher flowability, and the produced black yarns are uniform in color.