The utility model relates to a distribution automation terminal core unit capable of directly carrying out cold start-up at negative 40 DEG C. The distribution automation terminal core unit is characterized in that the output of a high speed sampling module in a circuit is connected with a low temperature starting module and a power supply module, a direct current of 48 V is input and passes through the power supply module, and then +/- 12V and 5 V outputs are achieved, a 5V output port is connected with a voltage stabilizing circuit composed of an inductor L2, a capacitor E4, a capacitor C10 and a capacitor C11, the voltage stabilizing circuit is configured in way that the capacitor C10, the capacitor C11 and the capacitor E4 are connected in parallel and then are connected in series with the inductor L2, and the voltage stabilizing circuit supplies power to a DC conversion chip. An industrial grade core unit processing chip which is good in low temperature resistance is employed, the distribution automation terminal core unit is capable of directly carrying out cold start-up in a low temperature environment at negative 40 DEG C.