Intimate partner violence (IPV) adversely impacts the physical and mental health of women globally. While the relationship between IPV and mental health outcomes has been established, less is known about the state of the literature from South Asia. This study aimed to collate and review evidence of the association of IPV with mental health in South Asian countries (Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka). Three electronic databases were searched for quantitative peer-reviewed studies published between 2013 and 2024. The review presents findings from 31 studies that assessed patterns among general populations of women, pregnant and postpartum women, and multiply marginalized women. Most of the studies were from India (n = 12) and Bangladesh (n = 11), with none from Bhutan or the Maldives. Significant relationships between IPV and poor mental health outcomes are evident in studies from all countries and across subpopulations. The most commonly assessed outcome was depression, but studies also looked at overall mental health, anxiety, stress, and suicidal ideation. While most studies focused on physical, sexual, and emotional or psychological IPV, a few examined IPV in the form of controlling behaviors and economic abuse. Some studies make important contributions to understanding overlapping forms of IPV and the underlying mechanisms through which they affect mental health. The variability in study designs, sampling strategies, measurements, and types of IPV makes drawing conclusions about the relationship between IPV and mental health difficult. Future South Asian studies must aim to reconcile these differences to improve policy and programmatic interventions.