An electronic component mounting apparatus comprising: a loading unit which is adapted to move a printed circuit board in a first horizontal direction to load the printed circuit board; a first substrate moving unit which is adapted to move the printed circuit board, loaded by the loading unit, in a second horizontal direction perpendicular to the first horizontal direction; a substrate holding unit which is adapted to temporarily hold the printed circuit board moved by the first substrate moving unit; a component mounting unit which is adapted to mount an electronic component on the printed circuit board held by the substrate holding unit; a second substrate moving unit which is adapted to move the printed circuit board with the electronic component mounted thereon in the second horizontal direction; and an unloading unit which is adapted to move the printed circuit board, moved by the second substrate moving unit, in the first horizontal direction to unload the printed circuit board, wherein the loading unit is adapted to receive the printed circuit board fed in the first direction from a device in a previous step, the electronic component mounting apparatus further comprises a base on which the loading unit, the first substrate moving unit, the substrate holding unit, the component mounting unit, the second substrate moving unit, and the unloading unit are placed, and the loading unit includes a conveyer for loading the printed circuit board, and the conveyer traverses the base in the first direction, characterized in that the loading unit, the first substrate moving unit, the substrate holding unit, the second substrate moving unit and the unloading unit are aligned in the second direction. a loading unit which is adapted to move a printed circuit board in a first horizontal direction to load the printed circuit board; a first substrate moving unit which is adapted to move the printed circuit board, loaded by the loading unit, in a second horizontal direction perpendicular to the first horizontal direction; a substrate holding unit which is adapted to temporarily hold the printed circuit board moved by the first substrate moving unit; a component mounting unit which is adapted to mount an electronic component on the printed circuit board held by the substrate holding unit; a second substrate moving unit which is adapted to move the printed circuit board with the electronic component mounted thereon in the second horizontal direction; and an unloading unit which is adapted to move the printed circuit board, moved by the second substrate moving unit, in the first horizontal direction to unload the printed circuit board, wherein the loading unit is adapted to receive the printed circuit board fed in the first direction from a device in a previous step, the electronic component mounting apparatus further comprises a base on which the loading unit, the first substrate moving unit, the substrate holding unit, the component mounting unit, the second substrate moving unit, and the unloading unit are placed, and the loading unit includes a conveyer for loading the printed circuit board, and the conveyer traverses the base in the first direction, characterized in that the loading unit, the first substrate moving unit, the substrate holding unit, the second substrate moving unit and the unloading unit are aligned in the second direction.