The invention discloses a radical benzene sulfonamide ethyl sulfuryl hydroxyethyl sulfate aniline compound and a preparation method thereof. The preparation method comprises the following steps: reacting acetanilide with chlorosulfonic acid and sulfoxide chloride to generate p-acetamido benzene sulfonyl chloride, and then condensing with sulfide generated through reaction between 2-chlorethamin hydrochloride and mercaptoethanol to obtain sulfur ether, re-oxidizing, etherifying or sulfonating the sulfur ether to obtain 2-[2-(4-amonibenzenesulfonamido)ethyl sulfuryl]hydroxyethyl sulfate or 2-[2-(4-amonibenzenesulfonamido)ethyl sulfuryl] hydroxyethyl sulfate-3-sulfonic acid. Comparing the active radical benzene sulfonamide ethyl sulfuryl hydroxyethyl sulfate aniline compound with 4-(2-sulfonylethanol sulfate)aniline; the synthesized reactive dye has bright colored light, and is low in substantivity, high in dye-uptake rate and fixation rate, less in hydrolysis dye, and excellent in various fastness indexes; especially, the light fastness, the soaping resistant fastness, and rubbing fastness are 0.5-1 level higher than ordinary variety.