IntroductionBlack women experience many barriers to receiving high‐quality maternal healthcare. The ability of Black women to self‐advocate may mitigate these threats to their health. Limited research describes Black women's self‐advocacy during the perinatal period and how self‐advocacy related to other relevant concepts. The aim of this study was to describe the relationship between self‐advocacy, patient–provider relationships, and mental health outcomes among Black women in the perinatal period.MethodsThis cross‐sectional descriptive pilot study recruited Black women who were either in their 3rd trimester of pregnancy or within a year postpartum to complete surveys describing their self‐advocacy (Female Self‐Advocacy in Cancer Survivorship Scale adapted for perinatal period) and maternal health outcomes (trust and comfort with maternal healthcare providers—Patient–Provider Relationship Scale; abuse and disrespect during childbirth—Mothers of Respect Index; experiences of discrimination—Experiences of Discrimination scale; depression—Edinburgh Postnatal Depression Scale; and postpartum posttraumatic stress—City Birth Trauma Scale).ResultsN = 40 participants were recruited between January and September 2022. Participants reported moderate levels of self‐advocacy which were associated with trust and comfort with healthcare providers (r = 0.57–0.76, p < 0.001). Feeling respected by healthcare providers was positively associated with two self‐advocacy subscales (r = 0.42–0.44, p < 0.01). Depression was inversely related to all self‐advocacy subscales (r = −0.47–0.62, p < 0.001).ConclusionBlack women's self‐advocacy during the perinatal period is associated with trust and comfort with healthcare providers, perceptions of respect from their providers, and perinatal depression. Future research should focus on promoting trusting, respectful relationships between Black women and their maternal health providers.