The invention discloses an alternating current power supply electronic clock with a power saving structure, comprising an electronic clock main body, which is characterized in that the electronic clock is provided with a power-switching circuit capable of saving power, the power-switching circuit is positioned outside the electronic clock main body and connected with the electronic clock circuit of the electronic clock, transfers the voltage of an urban electricity power supply circuit into a direct voltage consistent with the time oscillating frequency of the electronic clock and outputs thedirect voltage to the power output end of the electronic clock circuit. The power-switching circuit comprises a rectifying circuit, an auto-excitation type intermittent oscillation circuit, an outputcircuit and a feedback circuit, wherein the auto-excitation type intermittent oscillation circuit comprises a switch transformer T1, a flux reset circuit, a power regulation chip IC1 and a supply circuit of the power regulation chip. The invention has the characteristics of high electric energy transformation efficiency, obvious energy saving effect, high stability of output voltage, little source effect and load effect, small volume, light weight, global utilization and the like.