A radio frequency switch comprising: first to third ports (Tx, ANT, Rx) formed as first to third microstrip lines (111, 112, 113), respectively, which microstrip lines being formed on the upper surface of an dielectric substrate of the RF switch; a circulator having first to third nodes which are connected to the first to third ports (Tx, ANT, Rx), respectively; and a slot line pattern unit installed in a connection line between the third node of the circulator and the third port (Rx) so as to carry out signal transmission or interception, wherein the slot line pattern unit comprises: a first slot line which is formed on the lower surface of the dielectric substrate and which is provided at a first end thereof with an open slot having a circular cross-section so that signal transition occurs between the first slot line and a fourth microstrip line formed on the upper surface of the dielectric substrate and connected to the third node of the circulator; a loop-shaped slot line pattern unit formed on the lower surface of the dielectric substrate and connected to a second end of the first slot line so that signal transition occurs between the loop-shaped slot line pattern unit and the third microstrip line forming the third port (Rx) at a location of the loop-shaped slot line pattern unit which is opposite to a location of the loop-shaped slot line pattern unit connected to the first slot line, wherein the third microstrip line being formed as a terminal open circuit which has an open end extended by a length of λ/8 from the point of intersection between the loop-shaped slot line pattern unit and the microstrip line, thereby maximizing the magnetic field for signal transition at the point of intersection; and a switching circuit (C1, D1) which is installed at a predetermined location so as to transmit or intercept a signal by maintaining or short-circuiting a gap of the loop-shaped slot line pattern unit according to an external switching control signal; the switching circuit comprises first and second switching elements (C1, D1) each of which is installed at one side of the loop-shaped slot line pattern unit at a connection location between the loop-shaped slot line pattern unit and the first slot line so as to short-circuit a gap of the loop-shaped slot line pattern unit at the corresponding location. first to third ports (Tx, ANT, Rx) formed as first to third microstrip lines (111, 112, 113), respectively, which microstrip lines being formed on the upper surface of an dielectric substrate of the RF switch; a circulator having first to third nodes which are connected to the first to third ports (Tx, ANT, Rx), respectively; and a slot line pattern unit installed in a connection line between the third node of the circulator and the third port (Rx) so as to carry out signal transmission or interception, a first slot line which is formed on the lower surface of the dielectric substrate and which is provided at a first end thereof with an open slot having a circular cross-section so that signal transition occurs between the first slot line and a fourth microstrip line formed on the upper surface of the dielectric substrate and connected to the third node of the circulator; a loop-shaped slot line pattern unit formed on the lower surface of the dielectric substrate and connected to a second end of the first slot line so that signal transition occurs between the loop-shaped slot line pattern unit and the third microstrip line forming the third port (Rx) at a location of the loop-shaped slot line pattern unit which is opposite to a location of the loop-shaped slot line pattern unit connected to the first slot line, wherein the third microstrip line being formed as a terminal open circuit which has an open end extended by a length of λ/8 from the point of intersection between the loop-shaped slot line pattern unit and the microstrip line, thereby maximizing the magnetic field for signal transition at the point of intersection; and a switching circuit (C1, D1) which is installed at a predetermined location so as to transmit or intercept a signal by maintaining or short-circuiting a gap of the loop-shaped slot line pattern unit according to an external switching control signal; the switching circuit comprises first and second switching elements (C1, D1) each of which is installed at one side of the loop-shaped slot line pattern unit at a connection location between the loop-shaped slot line pattern unit and the first slot line so as to short-circuit a gap of the loop-shaped slot line pattern unit at the corresponding location.