Neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease (PD), remain major challenges in clinical neurology, as no definitive cure exists. Non-invasive brain stimulation (NIBS) techniques, including repetitive transcranial magnetic stimulation (rTMS), transcranial direct current stimulation (tDCS), and low-intensity focused ultrasound (LIFU), have emerged as promising therapeutic approaches for modulating cortical excitability and promoting neuroplasticity. rTMS appears to promote synaptic plasticity and increase regional cerebral blood flow, which may contribute to improved memory and executive function. tDCS also has demonstrated potential in enhancing cognitive abilities in AD by modulating cortical excitability via weak direct currents. LIFU, a novel and less explored NIBS method, has shown promise in preclinical and early clinical studies for neurodegenerative diseases. Recent findings suggest that LIFU may enhance cognitive function, facilitate neuroplasticity, and temporarily open the blood-brain barrier to improve drug delivery in AD. In PD, NIBS techniques have been explored to alleviate motor symptoms and improve dopaminergic function. rTMS applied to the motor cortex and supplementary motor area has been associated with improved motor performance, while tDCS has shown potential for enhancing motor functions. LIFU is under investigation for its ability to modulate deep brain structures which plays a key role in PD pathophysiology. This review aims to analyze recent advancements in NIBS applications for AD and PD, highlighting their potential clinical benefits and future directions in neurodegenerative disease management.