Purpose The purpose of this paper is to address the need for increased understanding, awareness and recognition of the autism female phenotype in terms of repetitive behaviours and restricted interests (RBRIs). Design/methodology/approach A systematic PRISMA review was conducted. The main aim of the present systematic review is to identify studies which have investigated RBRIs in females with autism spectrum disorder (ASD) or the differences in RBRIs between males and females with ASD. Findings In sum, 19 relevant articles were identified: 5 studies found no significant evidence to support the notion of sex differences in RRBIs in ASD; 1 study did not report any differences in RRBIs between males and females with ASD; 12 studies found evidence that males with ASD had significantly more RRBIs compared to females with ASD; and, lastly, 1 study found that girls with ASD have features of RRBIs which are exhibited more compared to boys with ASD. Research limitations/implications There is a real lack of in-depth knowledge and understanding of the female phenotype of ASD, and such lack of knowledge has a detrimental impact on the identification of autistic females and a lack of identification can have negative consequence. This is important to address in future research as it is well established that the earlier the diagnosis, the better the outcomes, due to the timely access to appropriate interventions. Practical implications The RBRIs exhibited in autistic females are not sufficiently captured by most currently diagnostic instruments. Clinicians are less likely to identify the RBRIs in females as they tend not to be the typical repetitive behaviours commonly associated with ASD. It has been recommended that clinicians consider “females as a whole” in terms of their clinical presentation and look for any indication of RBRIs, even repetitive interests which appear clinically innocuous. Originality/value There is relatively little research investigating RBRIs in autistic women and girls. There is a real need to highlight the importance of understanding and recognising how RBRIs can differ between males and females with ASD.