Ocular bacterial infections can cause a series of symptoms and signs, such as the formation of pus, conjunctival hyperemia, lid edema, and even visual impairment. The causative bacteria can come from the outside environment or from systemic infections transported by blood. The eyelid and conjunctiva have normal bacterial flora, of which disequilibrium facilitates external or intraocular infection. Bacteria of the normal microbiome can also cause infection, especially when they enter the aqueous humor or vitreous fluid. The eye may be infected from external sources or through an intra-ocular invasion of micro-organisms carried by the bloodstream. Bacteria are the most common agents causing external ocular infections, including blepharitis, keratitis, dacryocystitis, and orbital cellulitis. Bacteria are responsible for 70–80% of conjunctival morbidity which poses huge socioeconomic burdens to the general public Bacterial keratitis is the leading cause of corneal blindness. External ocular infections may remain localized, or progress to adjacent tissues. Bacterial ocular infections have been complicated by multidrug resistance; a problem that is intensifying over time. This poses a challenge in the clinical management of bacterial ocular infections.