Background Mistreatment and discrimination during childbirth are a global public health concern. Such experiences can adversely affect the subjective birth experience and increase the likelihood of compromised postpartum mental health, including symptoms of childbirth-related posttraumatic stress disorder (CB-PTSD) not only in mothers/birthing parents, but also in partners. This study examines instances of mistreatment and discrimination during childbirth, their association with CB-PTSD symptoms, and the potential mediating role of the subjective birth experience in both parents. Methods Data were retrieved from the prospective RESPECT_PARENTS cohort, a German community sample. For the current study, data from n = 1075 mothers/birthing parents and n = 454 partners, collected at two assessment points, i.e., during pregnancy and eight weeks after birth, were included. Regression and mediation models were used to analyze the associations separately for mothers/birthing parents and partners. Results Mistreatment during childbirth was reported by 25.8 % of mothers/birthing parents and 6.8 % of partners, whereas perceived discrimination was reported by 3.9 % of mothers/ birthing parents and 3.5 % of partners. These experiences predicted more severe CB-PTSD symptoms among mothers/ birthing parents. For both parents, experiencing more mistreatment and more discrimination was associated with a more negative subjective birth experience, which in turn was associated with more severe CB-PTSD symptoms, demonstrating a significant mediation effect. Conclusion The current study indicates that mistreatment and discrimination during childbirth exist in Germany among both mothers/birthing parents and partners, potentially contributing to a more negative subjective birth experience and more severe CB-PTSD symptoms. The findings emphasize the need to address mistreatment and discrimination during childbirth for both parents, in general and as potential risk factors for adverse outcomes.