The invention discloses a preparation method of the SON type metal-oxide semiconductor field transistor, including the steps of low temperature injecting the neon ion with secondary different energy in the large beam current, forming the void layer at the lower part of the active region after high temperature anneal; removing the silicon nitride side wall on the shallow trough insulation, preparing the MOSFET through the routine CMOS technology. The preparation method providing the SON type metal-oxide semiconductor field transistor can generate the air bubble with higher density due to the low dose Ne iron injection, adopts the low temperature with different energy to form two layers of air bubble belts, which combines to be the high relative density monolayer inanition after high temperature anneal, thereby forming the ultra-shallow junction SON structure with the heat emission channel with simple technology and low cost. Most steps are completed by the routine CMOS technology, whichis convenient for the large scale integrated circuit industrial production and reduced in the production cost.