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Methods obtaining gypsum whiskers via calcining dihydrate or hemihydrate gypsum perform high energy consumption. It also performs potential environmental impacts. New methods with energy-saving, high-efficiency, and environmentally friendly perform great challenges, which aim at fabricating gypsum whiskers even nanowhiskers. In this study, we used high-concentration calcium acetate solution and dilute sulfuric acid to fabricate anhydrite calcium sulfate nanowhiskers with microemulsion solution at room temperature. For further research on regulation and modification of its surface, calcium sulfates were modified by silicone quaternary ammonium salt and fatty acid methyl ester sulfonate in order to study their surface structure and crystal evolution during modification. After characterization, it indicated that the phase of calcium sulfate transmitted from anhydrite phase into dihydrite phase with a slight change on the surface layers. Benefiting from stability and activity properties of calcium sulfate nanowhiskers after modified, the compressive strength of cement paste with only 1% calcium sulfates performed increased absolutely 10.1% and 4.3% at conservation age of 3 days and 28 days.