Based on the application of light microscope observation of flocculation structure, the multi level flocculation structure model of fresh cement paste was constructed. Rotative viscometer was employed to measure the rheological parameters of fresh cement paste with different types of superplasticizers. The effect of different types of superplasticizers on the multi level flocculation structure of fresh cement paste was analyzed.The results show that if different types of superplasticizers are added in fresh cement paste, the hysteresis circle areas are variable in size, it is due to the different cohesion of cement particles. Different levels of flocculation structure in the fresh cement paste, and different types of superplasticizers can destroy different levels of flocculation structure. The better the dispersion of superplasticizer, the smaller the flocculation structure, the more evenly the dispersion,and the better the liquidity of fresh cement paste.