An additive C capable of changing microvia-filling method by TSV copper plating, and electroplating solution containing same. The additive C contains by mass percentage: 5%-10%, one of polyethylene glycol or polyvinyl alcohol with the molecular weight of 200-100,000, or the mixture with different molecular weight thereof; 0.001%-0.5% isomer of the surfactant which including the alkylphenol polyoxyethylene ether or fatty alcohol-polyoxyethylene ether; and the solvent is water. The electroplating solution containing the additive C could be used for microvia-filling by TSV copper plating, the electroplating current distribution could be adjusted reasonably to realize the smooth transition between the conformal and bottom-up plating, so as to reduce the possibility of the seam or void in the coating, realize the high-speed electroplating, reduce the thickness of the copper layer, reduce the TSV plating duration and the cost of the chemical mechanical polishing (CMP), and significantly improve the production efficiency.