The invention discloses high-performance concrete synergist. The high-performance concrete synergist is composed of, by weight, 5%-7% of dispersing component, 10%-15% of enhancing component, 3%-5% of activity stimulating component, 2%-4% of complexing component and the balance water. The invention further discloses a preparing method of the high-performance concrete synergist. The high-performance concrete synergist can effectively improve the workability of a concrete mixture, the strength of concrete and the comprehensive performance of the concrete. Under the premise that the strength of the concrete is ensured, the using amount of cement in the concrete can be reduced by 10%, and the using cost is reduced. Under the premise that the strength of the concrete is ensured, 40% of cement can be replaced by admixture (coal dust and mineral waste residues), and the cost is obviously reduced. The high-performance concrete synergist is wide in adaptability, obvious in effect enhancing function and obvious in economic benefit and social benefit.