The invention belongs to the technical fields of microbial immobilization and refractory wastewater treatment, and particularly relates to a manufacturing method and application of 3D self-assembled foam with embedded bacteria. The manufacturing method is simple in process, and the manufacturing cost for the 3D self-assembled foam with the embedded bacteria is low, so that high practical value isachieved; the 3D self-assembled foam with the embedded bacteria manufactured through the manufacturing method achieves high porosity, a large specific surface area, a high mechanical strength, high chemical stability, high hydrophily and high adsorptive performance, so that the mass transfer efficiency is much higher, the wastewater degradation rate and effects of the 3D self-assembled foam with the embedded bacteria are remarkably improved, and the loss of efficient strains during wastewater treatment is effectively reduced; and the 3D self-assembled foam with the embedded bacteria manufactured through the manufacturing method has a large bearing capacity, can be repeatedly used and can effectively reduce the effluent color contamination of biologically treated wastewater, so as to achieve great significance in large-scale application and intensified biological wastewater treatment.