Abstract :Aim :The aim of this study was to investigate the incidence of Middle mesial canal and Middle distal canal in mandibular molars and its influence on gender.Materials and Methods : This retrospective study was carried out at the department of Conservative Dentistry and Endodontics, Saveetha Dental College and hospitals, Chennai. Case records of 86,000 patients who had visited for dental treatment between 01-Jul-2019 and 31- March-2020 were assessed by SDC/SIHEC/2020/DIASDATA/0619-0320. Inclusion criteria for the study were presence of Middle Mesial Canal and Middle Distal Canal in mandibular molars. Records for each case were tabulated and after applying the inclusion criteria 25 case records were included in the study. This data was tabulated and analysed in SPSS and descriptive statistics was performed. Results :The results obtained were put into graphs and charts from the data which was exported to SPSS.After reviewing 8799 case records, data of 25 patients with Middle mesial canal and Middle distal canal were collected which showed that 14 patients were prevalent with Middle distal canal which was higher(56%) compared to Middle mesial canal(44%) in which 15 patients with MM & MD canal (60%) were seen in 36 which had higher prevalence with a higher male predilection (72%) . There was no association found between teeth number and MM & MD canal.(Chisquare value - 4.051a ; p-value = 0.256) (p>0.05) andgender with MM & MD canal.(Chisquare value - 0.005a ; p-value = 0.943) (p>0.05))Conclusion : The result of the study showed that out 44% of the patients had prevalence to Middle mesial canal and 69% with Middle distal canal with a higher incidence in 36 with a higher male predilection and no significant association was found for teeth number and gender with MM & MD canal. Hence, identification of the extra canals and their instrumentation is important in the prevention of unsuccessful treatment outcomes.