PURPOSE: To obtain a Schottky barrier diode in which the leak current can be suppressed low upon application of reverse voltage without varying the forward voltage characteristics.

CONSTITUTION: A plurality of small diameter Schottky barrier diode structures S, each comprising an anode electrode 2, a cathode electrode 3 and a guard ring 4 formed on the surface layer of a silicon pellet 1, are arranged on one pellet 1. In each structure S, the inner circumferential diameter (y) of the guard ring 4 is set to satisfy a relationship y≤2x, where (x) represents the thickness of a depletion layer 6 spreading at the PN junction between the P-type region of the guard ring 4 and the N-type region of the silicon pellet 1 upon application of reverse voltage. Since the Schottky junction between the silicon pellet 1 and the anode electrode 2 is concealed by the depletion layer 6 upon application of reverse voltage, leak current can be reduced.