Preparation method for green, environment-friendly and highly-efficient retardation type water reducer

The invention discloses a preparation method for a green, environment-friendly and highly-efficient retardation type water reducer. The method comprises the following steps: dissolving sucrose and p-aminobenzene sulfonic acid in water, carrying out reaction at 17 to 100 DEG C for 1 to 7 hours so as to obtain the green, environment-friendly and highly-efficient retardation type water reducer, wherein a mol ratio of the p-aminobenzene sulfonic acid to the sucrose is (0.1-1): 1. The water reducer prepared by using the method in the invention has water reducing and retarding effects, can realize different needs of projects according to different mixing amounts, and has good effects; meanwhile, the reducer has relatively-low cost and is free of formaldehyde pollution.