Overcurrent protection circuit

The invention relates to an overcurrent protection circuit. The circuit is formed by connecting a triode Q1, a resistor R1, a resistor R2 and a silicon-controlled rectifier Q2, wherein an input end I1 of the circuit is connected with one end of the first resistor R1 and a collector electrode of the triode Q1; the other end of the first resistor R1 is connected with a base electrode of the triode Q1 and an anode of the silicon-controlled rectifier Q2 respectively; an emitting electrode of the triode Q1 is connected with one end of the second resistor R2 and a control electrode of the silicon-controlled rectifier Q2 respectively; and the other end of the resistor R2 is connected with a cathode of the silicon-controlled rectifier Q2 and an output end I2 of the circuit. The overcurrent protection circuit has the advantages of simple structure, reasonable design, stable and reliable performance, low use energy consumption, obvious practical effect, low manufacturing cost, high anti-interference capacity and wide application range, difficultly interferes with other circuits or is difficultly interfered by other circuits, and can be applied to various current circuits for protection.