The invention provides a slip stitch adjusting device for a hosiery machine, which comprises a slip stitch lever, a rotary seat of the slip stitch lever, a height adjusting nut, a fixed seat, a guide plate, an adjusting screw of the guide plate, a hinge pine, a spring and one or a plurality of fasteners. According to the device, a mode that the height adjusting nut is additionally arranged between the rotary seat of the slip stitch lever and the fixed seat is adopted, so the fixed seat for inserting the rotary seat of the slip stitch lever in the prior art can be improved into an adjusting seat which can be freely adjusted, and accordingly, when the slip stitch lever is abraded or is not appropriately positioned during the use, the problems of time and labor wasting and the like due to discarding or additionally polishing or cutting the slip stitch lever because the position of the slip stitch lever cannot be adjusted are solved.