The invention discloses a large-width non-woven fabric bonding device and a bonding method thereof. The device comprises a feeding roller set and at least two non-woven fabrics, wherein the non-wovenfabrics are arranged on the feeding roller set for separation and transmission; an integrating roller, a pressing roller set and a receiving roller are arranged successively behind the feeding rollerset; an extruding head of a hot melt rubber extruder or a plastic extruder is arranged between the feeding roller set and the integrating roller; the extruding head is arranged on a side edge where the two non-woven fabrics are bonded; and the two non-woven fabrics are transmitted through the feeding roller set, pass through the extruding head, and then successively enter the integrating roller, the pressing roller set and the receiving roller. By adopting the technical scheme of the invention, automatic production of a large-width non-woven fabric is achieved, the non-woven fabric is in closebonding, and damage or tearing is not easily caused in the pulling process.