Narcissistic personality disorder as captured in categorical diagnostic systems (e.g., DSM-5) emphasizes grandiose features more associated with masculine norms and under-emphasizes vulnerable features more associated with femininity. This poses significant implications in diagnostic outcome and clinical treatment in women with narcissistic preoccupations. Research finds that clinicians using the DSM-5 categorical system tend to diagnose vulnerable narcissism in women as other 'feminized' personality disorders (e.g., borderline), but no research has explored gender differences in narcissism using the new ICD-11 dimensional framework for personality disorders. This study investigated the clinical utility of the ICD-11 approach in capturing gender differences in narcissistic presentations. Adopting an online vignette-based study, mental health clinicians (N = 157; 71.3% female) completed ratings of ICD-11 personality disorder severity and trait domains for two cases reflecting 'grandiose' and 'vulnerable' narcissism in hypothetical male or female patients. The results showed that ratings of core impairments in personality functioning and overall severity were consistent irrespective of patient or clinician gender, contrasting prior research using categorical models. While some differences were observed in trait domain (e.g., negative affectivity) between patient gender, these results suggest the clinical utility of the ICD-11 model as emphasizing elements of personality functioning in the process of assessment and diagnosis, therefore potentially being less susceptible to influences of gender stereotype in aiding clinical conceptualization.