A power-saving method and associated electronic device are provided. The electronic device is connected with a first external electronic device and a second external electronic device, and a first sensor and a second sensor are deployed on the first external electronic device and the second electronic device, respectively. The electronic device includes: a third sensor, and a processor, wherein the first, second, and third sensors have the same type. The processor gathers information from the first pedometer sensor, the second pedometer sensor, the first external electronic device, and the second external electronic device, and determines whether to turn off at least one of the first, second, and third pedometer sensors according to the information gathered.