Disclosed is a micro-coil assembly including a micro-coil unit which is inserted into an aneurysm or other vascular malformation of a patient and prevents inflow of blood by inducing thrombus, a coil pusher unit which is arranged adjacent to the micro-coil unit and delivers the micro-coil unit to the aneurysm or other vascular malformation of the patient, a tensile wire which is relatively movably arranged in the coil pusher unit, a tie which connects the micro-coil unit and the tensile wire, and a tie cutting unit which is arranged adjacent to the coil pusher unit such that at least a part of the tie cutting unit is movable between a setting position for maintaining the tie in a tied state and a cutting position for cutting the tie, and cuts the tie when moved to the cutting position.