A trocar wound closure system includes a suture passing needle and a guide for directing the needle through the wound site. A distal portion of the needle includes a capture rod with a slot. An obturator tube with a cutout section can be axially actuated to align the cutout section with the slot, and then moved out of alignment so as to capture the suture. The guide includes at least two tracks for directing the needle through the tissue track. A snare loop is located adjacent to the exit of each track, and configured to be actuated from a radially extended configuration to a retracted configuration so as to capture the suture section inserted through each loop. Radially expandable arms at distal section are movable between an expanded configuration and a slender configuration.