To provide a slab yarn capable of being produced by a usual spinning machine without requiring a special spinning frame and having the irregularity of natural feeling, a method for producing the same and a woven or knitted fabric by using the same.

This slab yarn having a natural feeling is produced by installing a concealing member at a collector in a roved yarn side of a front roller of the spinning frame, stopping the tip end of a part of the fiber of the roved yarn and bending the same so that the bent fiber becomes as a nodule and also the nodules are developed at random.