The invention provides a fin type field effect transistor and a manufacture method of the fin type field effect transistor. The method comprises the steps that a fin is formed on a semiconductor substrate, a virtual grid electrode is formed on the semiconductor substrate with the formed fin and stretches across the fin, first side walls are formed on two sides of the virtual grid electrode, ions are implanted in the fin so as to form a source electrode and a drain electrode of the fin type field effect transistor, the virtual grid electrode is eliminated, an opening is formed in the position of the virtual grid electrode, a high-K-grid medium layer and a metal grid electrode material layer are sequentially deposited so as to fill the opening, and a metal grid electrode is formed, and the first side walls and the high-K-grid medium layer on the side wall of the metal grid electrode are eliminated. According to the fin type field effect transistor, the high-K-grid medium layer on two sides of the metal grid electrode are effectively eliminated in sequence, stray capacitance is prevented from generating between the metal grid electrode and the source electrode or the drain electrode, other semiconductor structures are prevented from being damaged during the eliminating process, and the fin type field effect transistor is enabled to be good in electrical properties.