To provide mounting structure capable of preventing the damage in an external facing plate when the external facing plate is nailed and, at the same time, easily carrying out execution with a nail metal fixture.

Mounting structure of an external facing plate 3 is so constituted that the external facing plate 3 is mounted to the outside of an external wall 2 of a building 1 by a nail metal fixture 4, the nail metal fixture 4 is constituted of a head 8 and a main body 9 and that the front end 10 of the main body 9 is formed in a plane at right angles to the longitudinal axis. A spiral thread 11 is made on the circumference of the main body 9. A guide hole is made in a nailing section of the external facing plate in advance, and execution can be easily carried out by combining with the form of the nail metal fixture 4.