The utility model discloses a singlechip based energy saving circuit applied to occasions such as hotels and the like, which comprises a singlechip, a pyroelectric infrared sensing module, a single-pole double-throw relay, an energy saving lamp and a highlighting lamp, wherein a signal output end of the pyroelectric infrared sensing module is connected with an external interruption input end of the singlechip through a front-end inverter, and the output end of the singlechip is sequentially connected with the single-pole double-throw relay, the energy saving lamp and the highlighting lamp in series. The energy saving circuit disclosed by the utility model can realize that the energy saving lamp is turned on in the absence of people, the highlighting lamp is turned on in places where people stay, and the highlighting lamp is turned off in a delayed mode when people have walk away, thereby saving electricity.