The invention belongs to the field of antibacterial 
polymer materials and a 
processing method thereof, and particularly relates to a 
polyaniline composite antibacterial plastic as well as a preparation method and application thereof. The antibacterial plastic comprises a 
polyaniline main material and a 
polymer basis material, various forms of 
polyaniline or composite materials thereof, which are used as main antibacterial materials, and then are blended with other 
polymer basis materials, and then injection molding, 
blow molding, mould pressing, foaming and other 
plastic molding processes are carried out to obtain the 
polyaniline composite antibacterial environment purification material; and at a normal temperature, polyaniline can be dissolved or dispersed by solvents, and surface treatment is carried out on the plastic by being mixed with other polymers, for example, antibacterial antifouling and anticorrosive coatings and the like are manufactured through spray molding, 
casting, film painting, electrochemical deposition and other processes. The 
polyaniline composite material not only has an excellent 
antibacterial effect on 
escherichia coli, 
staphylococcus aureus, 
Candida albicans and the like, but also can be used as the environment purification material by utilizing the oxidoreduction characteristic to realize the removal of methanal, hydrothion, 
pollutant and other gases to keep the air fresh.