It began to have the notebook personal computer and the cellular phone used extensively for the electronic machine body, and the Mg-Al alloy material which was put to practical use and that it was represented by AZ91D suffered footlights. Though there is demand which became stable after that at present for the electronic machine body. It has proceeded with the development of None Chrome treatment to this magnesium alloy for about ten years, and it applies for the patent as a Ca-Mn phosphating in our company. It tried it, and December, 1999 could have line-ization as to the establishment of the low erectrical resistance film of None Chrome treatment line system for the notebook personal computer body. The technological outline about treatment system by this Ca-Mn phosphorus is reported by this paper. A result of a surface management examination about New material of magnesium alloy.