The invention discloses a power saving socket of an electric water heater. The power saving socket comprises an end L and an end N which are connected to a power supply 220V, and further comprises a first capacitor C1, bridge type rectifiers D1 to D4, a voltage stabilizing diode VD1, a second capacitor C2, a first photosensitive resistor VR1, a fifth resistor R5, a fourth resistor R4, a sixth resistor R6, a seventh resistor R7, a first triode Q1, a socket CZ1, a bidirectional controllable silicon VS1, a first resistor R1, a second resistor R2, a bidirectional triggering diode VB1, a photoelectric coupler IC1, a third resistor R3, a third capacitor C3, a sixth triode Q6, a second triode Q2, a ninth resistor R9, an eighth resistor R8, a third triode Q3, a tenth resistor R10, a fourth capacitor C4, a fourth triode D4, a fifth diode D5, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fifth triode Q5 and a touch point P1. The power saving socket is simple in circuit structure and good in actual application effect; the shortcoming that the existing socket has a single function is overcome, and the applicability is improved; the use cost is reduced, and the aim of energy conservation is fulfilled.