Purpose To date, some empirical studies showed a link between personality factors and frailty. Nevertheless, a systematic review is lacking synthesizing the current evidence. Consequently, the purpose of this review was to fill this gap in knowledge based on observational studies. Materials and methods Three electronic databases (PubMed, PsycINFO, CINAHL) were searched. Moreover, a hand search was conducted. Observational studies focusing on the association between personality and frailty were included, whereas disease-specific studies were excluded. Data referring to methods, characteristics of the sample and key findings were extracted. The NIH tool was used to assess study quality/risk of bias. Two reviewers performed study selection, extracted the data and conducted the quality assessment. Result: In sum, five (mostly longitudinal) studies were included in the final synthesis. Mainly based on large, nationally representative cohorts, these studies point to an association between personality and frailty. More precisely, they mainly point to a link between low conscientiousness as well as high neuroticism and increased frailty levels. The quality of the studies included was quite high. Conclusions This knowledge may assist in identifying individuals at risk for increased frailty levels (i.e., particularly individuals with low conscientiousness and high neuroticism). Efforts to increase conscientiousness and reduce neuroticism may assist in postponing frailty. Future studies are required to elucidate the underlying mechanisms. Prospero registration number: CRD42020193100.