The invention relates to a method for extracting zinc from high-cadmium zinc-contained mineral separation tailing water and preparing electric zinc. The method includes the following steps that (1) the high-cadmium zinc-contained mineral separation tailing water is filtered to remove suspended solid particles; (2) an organic phase is adopted for conducting two-stage counter-current extraction on aqueous phase feed liquid; (3) a sulfuric acid solution is used for conducting two-stage countercurrent washing on a loaded organic phase obtained after two-stage extraction; (4) a waste electrolyte is used for conducting reverse extraction on a washed organic phase; and (5) after strip liquor is subject to standing, ultrasonic treatment, air floatation treatment and activated carbon oil removing treatment, the oil content is controlled to be smaller than or equal to 1 mg/L, and then an electrodeposition process is executed to prepare the electric zinc. By means of the method, the problem of gypsum crystallization in the reverse extraction process is solved from a source, and stable running of the process is facilitated; and meanwhile, the process solves the problem in reusing of high-cadmium zinc-contained waste water, and is of great significance in perfecting and popularizing a process for treating lead and silver slag through a mineral separation method.