Abstract Self‐injurious behaviors (SIB) encompass a heterogeneous set of self‐inflicted aggressive behaviors that are highly prevalent in autistic youth. Existing research on SIB in autism spectrum disorder (ASD) has been limited by significant methodological and conceptual inconsistencies. Thus, the current study leveraged item‐level data capturing the severity of unique SIB topographies to further understanding of factors associated with distinct SIB in a sample of 582 autistic youth ( M age = 12.12, SD age = 3.68; range: 3–19 years; 13% females). Results suggest variation in severity endorsements for specific SIB topographies amongst autistic youth, such that 30%–50% of caregivers endorsed slight to very serious concern regarding the SIB topographies of bites nails/skin/fingers, scratches self, hits head/face/neck, bangs head against things, and picks skin. Generalized additive models demonstrated distinct patterns of associations between each SIB topography and dysregulation, sensory hypersensitivity, age, sex, IQ, and language level. Findings underscore the importance of exploring SIB as a multifaceted construct to capture unique correlates of distinct SIB that vary in severity and functional impact, which is critical for the development of effective interventions. This study represents an important step towards more individualized characterization of SIB and support for diverse presentations of these behaviors in autistic youth.