Treatment of micro-polluted water is considered to be a vital issue and has attracted more and more attentions around the world. The turbidity and humus affect the quality of drinking water. As a widely used type of water treatment technology, coagulation is known for safety, practical and high-efficiency, and has been considered as a prospective technology for micro-polluted water. Coagulants are the core of coagulation technology and choosing a suitable coagulant to achieve high coagulation efficiency in the treatment process is crucial. Different kinds of coagulants, coagulants containing aluminum such as aluminum sulfate (AS) and polyaluminum chloride (PAC), coagulants containing ferric such as ferric chloride and polyferric chloride (PFC) were applied, and then followed by compound of coagulant aid polyacrylamide (PAM) and activated silicic acid (ASI) respectively. These coagulant aid possess good adsorption bridging ability and can improve the flocculation efficiency greatly to a certain extent. And in this work, turbidity, UV₂₅₄ and floc size were investigated to indicate the coagulation efficiency. The optimum coagulation conditions are determined as follows: AS dosage of 22 mg/L, PAC dosage of 18 mg/L, FeCl₃ dosage of 16 mg/L, and PFC dosage of 8 mg/L when used alone. PAM dosage of 0.1, 0.1, 0.05, 0.2 mg/L respectively when compounded with PAM. ASI dosage of 0.5, 1.5, 1.0, 1.0 mg/L respectively when compounded with ASI. In general, large amounts of humic acid are produced by the degradation of organic matter for aquatic organisms, and as a result, the water quality are seriously endangered. Thus, the removal of humic acid from wastewater has become imperative. In the passage, two common coagulants, PAC and PAM were applied in the treatment of humic acid wastewater, and PAC compounded with PAM was explored too. Same as before, the coagulation effect was determined by the measure of turbidity and floc size. The result shows that the optimal coagulation efficiency is achieved with PAM dosage of 8 mg/L, PAC dosage of 100 mg/L respectively when used alone. PAM dosage of 0.8 mg/L when compounded with PAC. The result shows that the compound can effectively enhance the coagulation effect at low dosage.