Small incision cataract surgery has been widely used as the development of the technology. The impetus behind smaller cataract incisions includes diminished ocular surgical trauma, faster visual recovery through rapid wound stabilization and less induced astigmatism. Foldable intraocular lenses made of several different materials has been used as the development of phacoemulsification. Although the incidenceof infectious endophthalmitis has been lowered significantly, endophthalmitis is still one of the most serious complications after cataract surgery and intraocular lens implantation.Objectives To investigate the influence of different methods (forceps vs injectors) on the bacterial contamination during foldable intraocular lens (IOL) implantation, and to compare the influence of these two methods on IOL surface as well as bacteria adherence to IOL surface through an in vitro experiment.Methods A. A Foldable IOL was implanted by forceps or an injector into a surface-bacteria-contaminated model eye, the bacteria carried by the IOL were counted by a quantitative-culture method. B. After the IOL was implanted by these two methods into a sterile model eye, the IOL was taken out and put into a bacterial suspension. The IOL surface was then analyzed under scanning electron microscope (SEM) and the bacteria adhered to the surface was again counted.Results A. When forceps or an injector was used, the bacteria number carried by a IOL into the contaminated model eye was 2621 ± 902 and 320±38 per IOL, respectively. The difference was statistically significant (P = 0.004) . B. After being implanted by forceps or an injector into a sterile model eye followed by bacteria adherence, the bacteria number on the IOL surface was 5477 ± 1842 and 1337 ± 756 per IOL, respectively. The difference was again statistically significant (P =0.000) .SEM examination showed clear folds with clusters of bacteria on the surface of 3 IOLs from 6 that were implanted by forceps, while this could not be found on any of the 4 IOLs that were implanted by an injector.Conclusion When compared to forceps, the use of IOL injector can reduce bacterial contamination and adherence during IOL implantation, which may theoretically reduce the risk of bacterial infection after cataract surgery.