The slump loss of fresh concrete mixed with superplasticizers should be well controlled to ensure its transportation and pumping. In this paper, we describe a comprehensive overview of the mechanism of fluidity loss and then analyze the reason for the change. Researches show that the slump loss of fresh concrete is influenced by the mineral composition of cement clinker, the type and characteristics of aggregate, the species and dosage of admixture, the mix proportion and the construction environment, etc. Thus, a series of methods proven to be effective, such as adjustment of raw materials, adding methods of chemical admixture, synthesis of new types of superplasticizers, etc. have been proposed to solve the problems.