The invention discloses a network filter and a manufacture technology thereof. The network filter comprises two transformer coils, a choking coil and electric wires wound to the coil, wherein the primary winding incoming line terminals of the two transformer coils are the input ends of the network filter, and the secondary winding outgoing line terminal of the choking coil is the output end of thenetwork filter; the connection way of the two transformer coils and one choking coil is that the secondary winding outgoing line terminals of the two transformer coils are jointly connected with theprimary winding incoming line terminal of the choking coil; or after the secondary winding difference lines of the two transformer coils are twisted, the secondary winding difference lines are simultaneously jointly wound to the choking coil. By use of the network filter, the original design of two choking coils and two channels is simplified, cost is lowered, and performance is improved.