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The basic principle of complex extraction is to take advantage of the difference in solubility of organic substances in wastewater between the extractant and water, so that these organic substances are absorbed by the extractant. Under alkaline conditions, these organic substances react with the base and end up in the back-extraction solution, where they can be separated and concentrated. This method has a high extraction efficiency, and its back-extraction rate using alkaline solutions is also high; therefore, it is suitable for treating toxic, highly concentrated, and difficult-to-degrade organic wastewater. However, it is often difficult to treat organic wastewater using traditional extractants, as the organic phase separates into two layers during the extraction process, which hinders the progress of the extraction reaction. We employed an extractant of our own development, which not only retains the advantages of conventional extractants but, most importantly, solves the problem of phase separation in the organic phase, yielding satisfactory results. By carrying out extraction processes, we manage to concentrate, separate, and recover the valuable organic compounds present in wastewater, thereby reducing resource waste. This approach not only enables the treatment of wastewater but also allows us to offset the costs associated with wastewater treatment by utilizing the value of the recovered organic compounds. The wastewater treated by this process shares a common characteristic: the organic substances in it often contain phenol hydroxyl groups, carboxylic acid groups, or sulfonic acid groups; it has a high concentration, high color intensity, a high content of inorganic salts, and poor biochemical properties. Various wastewater treatment processes have been operating smoothly, not only resolving the environmental issues related to sewage discharge for manufacturers but also effectively recovering valuable chemical substances from the wastewater, thereby achieving excellent social and economic benefits. The main economic and technical parameters of this process (which may vary depending on the wastewater being treated) are as follows: 1. The extractant is inexpensive, requires low consumption, no special equipment is needed, the operation is simple, and the treatment costs are low. 2. Generally, the COD of raw wastewater is between 40,000 and 50,000; after extraction treatment, the COD of the treated water can be reduced to several hundred, with an extraction efficiency of over 99%. 3. The color and acidity of the wastewater have both been reduced. 4. This process recovers valuable organic substances from wastewater, which not only helps to cover the costs associated with wastewater treatment but also generates certain economic benefits for the enterprise.