Background and Aim: Personality disorders (PDs) are widespread, rigid, and maladaptive with collections of traits that impair individuals and limit their capacity to function effectively. Recent studiesindicate that PDs are consistently associated with several demographic characteristics. The present study was conducted toinvestigate the differences between the demographic characteristics of DSM-5 Sections II and III PDs in an Iranian clinical sample. Materials and Methods: Data on the demographic distribution of DSM-5 Sections II and III PDs were derived from a total of 430 Iranian patients with PDs presenting to four clinical centers in Tehran using well-established measures. Different statistical analysis methods were used to compare demographic differences between DSM-5 Sections II and III PDs. These analyzes were performed using SPSS software V. 22. Results: Data analysis indicated that educational level, gender, age, marital status, average monthly household costs, and ethnicity had an impact on most PDs. In return, birth order accounted for the changes in only DSM-5 Section II histrionic PD. Conclusion: Current research reveals that certain demographic subgroups have an impact on PDs. Accordingly, the need for psychiatric services for these individuals needs to be explored.