The utility model provides a string-type groove trapping filter tip, which consists of a tow core rod (1) and wrap paper (6) coated outside. A layer of inner paper (2) coated on the tow core rod is arranged between the tow core rod and the wrap paper. The inner paper (2) is provided with 1 to 10 sections of groove groups. Each section of groove groups consists of 1 to 50 longitudinal grooves (4) which are arranged along the circumferential direction of the tow core rod. Dense small drainage holes are distributed on both end faces and both walls of the longitudinal grooves. The longitudinal grooves are sunken into tows, compress the tow core rod, make the center density increased and force part of smoke to enter the longitudinal grooves with lower suction resistance through the small drainage holes, flow into the grooves from fibers of the filter tip repeatedly, then flow into the fibers from the grooves, repeat the process again and again and be continuously acted on by tar reduction mechanisms such as diffusion deposition, dense flowing, small hole amplification and the like so as to furthest take the comprehensive effects of reducing tar and reducing damage of the fiber filter tip.