Disclosed is an intervertebral fusion cage which may be inserted between vertebrae from which a disk is removed to restore and maintain an interval between two vertebrae, and more specifically, to an intervertebral fusion cage having an easily mountable shape while enlarging a contact area with blood in a spinal cavity during surgery. A intervertebral fusion cage 100 generally includes a front part 102, first and second side parts 106 and 108 connected to both ends of the front part 102, and a rear part 104 connected to the pair of first and second side parts 106 and 108, wherein the front part 102, the first and second side parts 106 and 108 and the rear part 104 define fixing holes 130 and 132 therein which are vertically opened.