Potentially morally injurious events (PMIEs) are experiences that violate deeply held moral values through one's own transgressive actions (commission), failing to prevent or witnessing wrongdoing (omission), or betrayal by a trusted person. PMIE exposure has been linked to psychological distress, but it is unclear whether different PMIE subtypes confer distinct patterns of risk. This systematic review examined associations between specific PMIE subtypes and key psychological outcomes. Multiple databases were searched for quantitative studies that assessed PMIE subtypes in relation to PTSD or complex PTSD, depression, anxiety, alcohol misuse, and suicidal ideation or self-injurious behaviour. Fifteen studies published in the last seven years (total ≈ 21,700) in military, healthcare, veteran, and civilian samples met inclusion criteria. A Population-Exposure-Outcome framework guided data extraction, and findings were synthesised narratively by outcome and subtype. Betrayal-type PMIEs were frequently associated with PTSD, depression, and anxiety across included studies. Commission-type events were associated with several outcomes, including PTSD, depression, and suicidality, although findings varied across samples and analytic approaches. Omission-type exposures showed more variable associations overall, although several studies reported significant links with PTSD, depression, anxiety, or suicidality. PMIE subtypes showed overlapping but potentially different patterns of associations with psychological distress. Across the available literature, betrayal-related PMIEs emerge as the most prominent and consistent correlate of PTSD, depression, and anxiety, while commission-related events were also linked with distress, particularly suicidality, and omission-related findings were less consistent. These findings support considering PMIE subtypes separately in assessment and future research.