AIM: To evaluate the pathogens in cultured Jones tubes used in lacrimal bypass surgery according to the postoperative periods and to obtain data for the prevention of infection of functional lacrimal stent invention. METHODS: Totally 71 patients (81 eyes) who underwent the removal of Jones tubes were enrolled in study. All the removed Jones tubes were cultured for bacterial and fungal identification and tested for bacterial antibiotic sensitivity. The results were analyzed according to the duration of the inserted Jones tube after lacrimal bypass surgery. RESULTS: Of the 81 eyes, bacteria were isolated from 69 eyes (85.2%) and fungi from 6 eyes (7.4%). Among 69 eyes, 40.6% showed Staphylococcus aureus (S. aureus), 11.6% were Pseudomonas aeruginosa (P. aeruginosa). Gram-positive bacteria were isolated more than Gram-negative bacteria, but Gram-negative bacteria showed a higher incidence in the Jones tube implanted for over 10y (P=0.035). The antibiotic sensitivity test showed that 46.4% of S. aureus were resistant to oxacillin. In terms of antibiotics commonly used in ocular clinical practice, vancomycin was sensitive to S. aureus and Streptococcus pneumoniae (S. pneumoniae), amikacin responded to P. aeruginosa and Proteus mirabilis (P. mirabilis). Trimethoprim/sulfamethoxazole (TMP/SMX) was all sensitive to S. aureus, S. pneumoniae and P. mirabilis except P. aeruginosa. CONCLUSION: S. aureus is the most commonly found organism in the Jones tube after lacrimal bypass surgery, and 46.4% of them are methicillin-resistant S. aureus (MRSA), sensitive to vancomycin. Especially, P. mirabilis responded with amikacin is dominantly detected in the Jones tubes implanted for more than 10y.