Abstract: A knitted fabric having a heat generating function has a four-layer structure and can be knitted by a flat knitting machine. Knit stitching is used to knit first and second layers such that the second layer is fully covered under the first layer. Tuck stitching is used to knit the third layer such that one stitch is made to the third layer per a preset number of stitches made to each of first and second layers. Knit stitching is used to knit the fourth layer. After knitting, the fabric is soaked with water and spin-dried to form protrusions, spatially distributed as a centered rectangular lattice, on fabric surface. The second layer is electrically conductive for generating heat and is hidden inside the fabric. This layer is not easily hooked by a user during use and cleaning. The fabric is elastic and soft, and provides a comfortable feeling to the user.