The invention provides an alkenyl alkyl phenol polyoxyethylene ether and a preparation method thereof, and belongs to the technical field of oil exploitation. The alkenyl alkyl phenol polyoxyethylene ether has a structural formula 1 shown in the specification, wherein m is 6-14, and n is 8-14. The alkenyl alkyl phenol polyoxyethylene ether provided by the invention can generate polymerization reaction with acrylic amide; the prepared polymer is affected a little by external metal ions, and has good salt resistance; the temperature resistance and salt tolerance of the polymer can be effectively improved.