Acid soil improver

The invention provides an acid soil improver. The acid soil improver is prepared from the following components in percentage by weight: 25 to 43 percent of semi-dry flue gas desulfurization ash, 1 to30 percent of straw, 1 to 30 percent of oyster shell, 6 to 15 percent of magnesium sulfate and 6 to 15 percent of zinc sulfate. The invention provides the acid soil improver which takes the semi-dry flue gas desulfurization ash as a main component, the acid soil improver is capable of improving the acidity of acid soil and preventing food production reduction caused by degradation of the acid soil, and meanwhile, resource utilization of the semi-dry flue gas desulfurization ash is promoted.