Endophthalmitis is one of the most serious complications of the ocular surgery leading in most cases to a significant decrease in vision. The use of preoperative antibiotics and / or povidone-iodine has been advocated as an effective measure to prevent endophthalmitis, although it was never proved in a prospective trial. The additional benefit of topical preoperative antibiotics to povidone-iodine alone is controversial, and should be balanced with the risk of producing antibacterial resistance, the increasing problem of modern medicine. It was shown that 3 days preoperative use of major antibiotics is as effective as 1 hr preoperative use; povidone-iodine is as effective as antibiotic; single 5% povidone-iodine use is less effective than twice irrigation with the same solution; 10% povidone–iodine is more effective than 1% poviodone-iodine. Moreover, preoperative antibiotic use did not lower the endophthalmitis rate. In conclusion, adding the antibiotic to povidone-iodine brings no clear benefit. The antimicrobial resistance is known to be produced by repeated, overused and extended use of antibiotics, and might lead to development of treatment resistant infections, including severe forms of endophthalmitis.