Maternal personality plays a role in how a mother parents her children and adolescents. Current trait-based measures of personality are acceptable for use in maternal samples, but the presence or absence of given personality traits might not be enough to describe how personality relates to parenting. The Level of Personality Functioning Scale (LPFS) could serve as a solution, as it was designed to capture level of dysfunction in personality without being reliant on specific personality traits. Research, however, has yet to demonstrate the LPFS as a useful measure of personality in maternal samples, thus the goal of this study. A sample of 123 mothers reported on behavioral problems in their adolescent-aged children and their own personality using both a trait-based measure and the LPFS. Our data showed that maternal reports on the LPFS were associated with maternal perceptions of adolescent behavioral problems, in addition to being an acceptable measure of personality in our maternal sample. We also provide support for incremental validity of the LPFS in our sample, as the LPFS uniquely predicted maternal perceptions of adolescent behavioral problems even after controlling for maternal personality traits. Our results are discussed in light of the limitations of the extant work on maternal personality and add to the literature by demonstrating that the LPFS is an acceptable and ubiquitous measure of personality in maternal samples.