Cerebral stroke, a severe cerebrovascular disease causing acute brain dysfunction, imposes a heavy burden on families and society due to its high incidence and disability rates. Patients often develop post-stroke cognitive impairment (PSCI) after stroke, which affects multiple cognitive dimensions including memory, executive function, attention, language, and visuospatial abilities. Traditional rehabilitation therapies, although somewhat effective in promoting cognitive recovery, generally suffer from slow onset, long treatment cycles, and patient compliance issues. In recent years, repetitive transcranial magnetic stimulation (rTMS), as an emerging neuromodulation technique, has shown positive effects on the cognitive function of PSCI patients by continuously applying high-intensity, transient magnetic pulses to the brain tissue, effectively modulating the excitatory state of the cerebral cortex. This review aims to summarize the mechanisms of action and clinical research progress of rTMS in the treatment of PSCI, providing a scientific basis for clinical treatment planning and inspiring future research directions.