A method for high-speed vacuum unitary packaging of portion-cut meats, wherein a vacuum four-side sealed object containing a plurality of portion-cut meats obtained by dividing a livestock meat, such as beef, pork, chicken, or the like, or a large-size fish into many portions is divided into four-side sealed objects with vacuum being maintained at high speed using an impulse sealer for vacuum unitary packaging. Two or more portion-cut meats are loaded on conveying means with a prescribed spacing being given between portion-cut meats; a vacuum four-side sealed object is formed by using upper and lower wrapping films having gas-barrier properties and inner surface thermal fusion bonding properties to integrally vacuum package the portion-cut meats; a flat part between portion-cut meats in the vacuum four-side sealed object is fusion bonded by using a heat impulse sealer for heating film layers from both above and under to form two or more seal lines; and the films between the two or more seal lines are secondary cut; a second energization of lower heater wires and secondary cutting being simultaneously carried out after a first energization of upper heater wires being completed, or a second energization of upper heater wires and secondary cutting being simultaneously carried out after a first energization of lower heater wires being completed.