Background: Fixed orthodontic appliance has a much more complex design to clean rather than the removable orthodontic appliance, which makes the people with fixed orthodontic appliance face more inconvenience with preserving the mouth cavity hygiene during the treatment period. The poorly preserved mouth and tooth hygiene during the treatment period may cause problems to the mouth cavity, such as tooth caries, gingival hyperplasia, periodontal damage, and plaque buildup. Research Objective: To understand the dental caries status in UMY medical faculty students with fixed orthodontic appliance. Research Methodology: The research is a non-analytical descriptive research with cross sectional research design. There were 45 samples that were taken by using total sampling technique. The research subjects were the medical faculty students with fixed orthodontic appliance in UMY. The tooth caries status was measured by using DMF-T index. Result: Based on WHO’s DMF-T examination standard, the 45 research subjects can be categorized by its tooth caries intensity with DMF-T average score by 4,5, which may be included into high category (4,5 – 6,5). Conclusion: The average DMF-T index on UMY medical faculty students fixed orthodontic appliance is 4,5. This number may be categorized into a high category according to WHO’s standard (4,5 – 6,5).