An anchor plate mounting structure of a vehicle seatbelt includes an anchor plate that is provided on a mounting portion provided on a surrounding portion of a vehicle seat, and has a belt connecting portion to which an end portion of a lap belt of the vehicle seatbelt, the lap belt corresponding to a waist of an occupant, is fastened; a fastening portion that is provided in a position away from the belt connecting portion, and by which the anchor plate is fastened to the mounting portion; and a rotation-stopping portion that is provided in a position away from both the belt connecting portion and the fastening portion, and by which the anchor plate engages with a mounting portion side. An alignment direction of the belt connecting portion and the fastening portion intersects with an alignment direction of the fastening portion and the rotation-stopping portion.