Abstract: The fractal structure characteristics of flocs have a significant impact on floc sedimentation and compaction dewatering behavior. Currently, conventional experimental methods struggle to accurately analyze the micro−flocculation process. To overcome this limitation, a numerical model and simulation approach of floc fractal growth was established by the Computational Fluid Dynamic−Discrete Element Method (CFD−DEM) coupling approach based on the experiment validation. By employing the proposed numerical model, the flocculation behavior of fine mineral particles in a typical zone of a lab−scale flocculation stirrer was numerically investigated. The typical zone was identified at the outer edge of the impeller, which exhibits the highest turbulent intensity. By analyzing important parameters such as the statistical number of particle coordination number, the voidage and effective density of flocs under different stirring speeds, the fractal growth and evolution laws of flocs, the motion behavior of flocs and the settling mechanisms were revealed deeply. The results show that under a certain stirring speed, when the particle coordination number is less than 3, there is a positive correlation between the particle coordination number and the stirring speed; When the particle coordination number is greater than 5, there is a negative correlation. Within the range of studied stirring speeds from 250 r/min to 450 r/min, the mean floc size presents a decreasing tend with the increase in stirring speed. The voidage of flocs is positively correlated with the number of sub−particles in the flocs, exactly exhibiting a power function relationship with an exponent less than 1. However, the effective density is in a power−law decreasing function relationship with the equivalent diameter of flocs. This study can not only provide a strong theoretical basis for a deeper understanding of the mechanism of fractal growth of flocs and flocculation process regulation, but also provide the technical guidance for the industrial flocculation process.