Embodiments of the invention disclose an ECG device, an ECG signal processing method, an ECG lead signal generating circuit, an ECG signal generating method, another ECG device, another ECG signal processing method, and an ECG electrode assembly. The ECG device has an electrode assembly and an ECG lead signal generating circuit. The electrode assembly has three cardio enclosure electrodes for acquiring three cardio enclosure voltages, respectively. The ECG lead signal generating circuit has a first precordial lead generator. The first precordial lead generator is configured to generate a first modified precordial lead according to the three cardio enclosure voltages, wherein the three cardio enclosure voltages are sufficient for generating the first modified precordial lead.
