The invention provides a floss fusing device for a floss machine. The device comprises a floss pick upper die and a floss pick lower die, wherein a heating rod connecting plate is arranged above the floss pick upper die, the top of the heating rod connecting plate is provided with an air cylinder driving the heating rod connecting plate to move vertically, the heating rod connecting plate is connected with a hollow heating rod, the top end of the hollow heating rod is connected with an external air source, the positions, corresponding to the hollow heating rod, of the floss pick upper die andfloss pick lower die are provided with pore canals allowing the bottom of the hollow heating rod to be inserted in, and the hollow heating rod is located above the fused portion of the thread residueof a floss pick after extending into the pore canals. The floss fusing device for the floss machine firstly creates a non-contact type fusing method in the industry, avoids a series of defects of thecontact type fusing, and can effectively control the pulling force of a floss made from a nylon thread or a polyester thread material to ensure the flat shape of the floss, so that the thread residueof the floss is perfectly integrated with a product, and the floss pick product has a very perfect surface and standard-compliant quality and height.