The invention discloses a coated silicon carbon electrode of a lithium-ion battery. The coated silicon carbon electrode is composed of a current collector, a silicon carbon layer and a coating. The current collector in the middle is a sheet-like skeleton member. The front and back surfaces of the current collector are provided with negative silicon carbon layers and the current collector and the negative silicon carbon layers are molded through rolling. The coating is a conductive coating. The conductive coating coats the surface of the negative silicon carbon layer and has thickness of 2-15 micrometers after drying. The invention also relates to a formula of the conductive coating. The formula comprises, by weight, 2 to 10% of PVDF, 2 to 15% of a carbon material and 75 to 94% of NMP. Through use of the conductive coating on the silicon carbon layer, when the silicon carbon layer of a battery is cracked or pulverized in circulation, the conductive coating can produce a certain conductive function. Therefore, the coated silicon carbon electrode prolongs a service life of the negative silicon carbon electrode and prolongs the cycle life of a matched battery.