The invention belongs to the technical field of environment protection and particularly relates to a method for treating zinc-containing wastewater by utilizing granular sludge formed through microbiological flocculation. In the chemical precipitation treatment process of the zinc-containing wastewater, efficient gathering of precipitates is the key to formation of rapidly precipitated granular sludge. Therefore, microorganism-based filamentous fungi which have branched network structures and have higher non-covalent bond action with micro-nano particles are applied to the forming process of chemically precipitated granular sludge, and the filamentous fungi are low in cost, widely sourced, stable in property and convenient for large-scale application. The sedimentation rates of chemically precipitated granular sludge obtained with a living filamentous fungus method and chemically precipitated granular sludge obtained with a dead filamentous fungus method reach 3.2 cm/s and 3.0 cm/s respectively and are far higher than that of flocculent sludge. Thus, the method is a cheap, safe and efficient method for promoting formation of chemically precipitated granular sludge.