Abstract:[Objective] To investigate the capacity of different bacteria-culture samplings in debridement to determine the pathogenicbacteria of foot chronic osteomyelitis. [Methods] Clinical data of 105 patients with chronic osteomyelitis of the foot from October 2017 toFebruary 2022 were retrospectively analyzed. A total of 105 bacterial cultures were sent for examination, including 29 (1 set), 36 (3 sets) and40 (5 sets). The number of bacteria detected and the ability to detect pathogenic bacteria were compared. [Results] Bacteria were detected in82 of 105 patients with chronic osteomyelitis, among which Staphylococcus aureus accounted for 34.2% of the total detected bacteria, fol-lowed by Staphylococcus epidermidis accounted for 12.2%. In the 105 samples, the detection rate of each set of bacteria was 65.5% (1 set),75.0% (3 sets), and 90.5% (5 sets). The capacity to identify pathogenic bacteria was 85.0% (5 sets), 55.6% (3 sets), which were statisticallysignificant between 1 set and 5 sets, as well as 3 sets and 5 sets (P＜0.05), whereas not significant between 1 set and 3 sets (P＞0.05). [Con-clusion] In the detection of pathogenic bacteria, the ability of sending 5 sets of specimens for intraoperative detection is the strongest, whilesending 1 set of specimens for intraoperative detection is the worst. Therefore, when determining pathogenic bacteria, it is recommended totake multi-site samples during debridement and send at least 5 sets of bacterial samples for examination.