BackgroundMultiple mini interviews (MMI) is a structured student selection method where applicants rotate around a series of stations that do not require previously learned knowledge. The Big Five Inventory (BFI) is a tool often used to measure personality traits commonly used in applicant selection.ObjectiveThe aim of the current study was to assess the effect of personality traits using the BFI on undergraduate dental students’ performance in MMI.MethodsThis research was conducted at The Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia. All undergraduates applying to the dental program at King Abdulaziz University, Faculty of Dentistry (KAUFD) in two academic years [(2014–2015) and (2015–2016)] undertook the MMI held at KAUFD and completed the BFI inventory with a total number of 350 students. The MMI consisted of five stations while the BFI contained forty-four items. Data were analysed by SPSS version 20, using independent-samples t-test, Mann-Whitney U test, Spearman’s rho correlation coefficient and Chi-square test.Resultsfemale students scored higher than their male counterparts but scores were only significant in the empathy station (p<0.001) in the first year, and in both empathetic skills and team work abilities (p<0.05) in the second. BFI results indicate that male students scored higher on agreeableness (p<0.003) and lower on neuroticism (p<0.001) in the first year while female students scored higher on agreeableness and conscientiousness (p<0.001) in the second year. Students of private schools had higher total MMI scores compared to those of public schools (p<0.05).ConclusionMMI combined with the Big Five Inventory can be a useful tool in the admission process.