Alzheimer's disease (AD) is a leading cause of dementia, characterized by neuronal degeneration and atrophy. Matrix metalloproteinases (MMPs), proteolytic enzymes involved in extracellular matrix remodeling, have been implicated in AD pathophysiology. This review aims to summarize recent research on the role of MMPs in AD, focusing on cell culture studies and human studies. MMPs are classified into six groups based on their structure, localization, and substrate specificity. They play crucial roles in various physiological and pathological processes, including ECM remodeling, inflammation, and signaling pathways. In AD, MMPs are upregulated in response to Aβ peptides, with MMP-9 showing potential neuroprotective effects by degrading Aβ fibrils. Cell culture studies have demonstrated that MMPs can influence APP processing and tau protein aggregation, suggesting their involvement in AD pathology. Postmortem brain tissue analysis revealed higher MMP-1, MMP-9, and MMP-3 concentrations in AD patients compared to controls, particularly in regions affected by amyloid plaques and neurofibrillary tangles. In plasma and cerebrospinal fluid (CSF), MMP-10 and MMP-9 levels were elevated in AD patients, potentially serving as biomarkers for disease progression. Sex differences were also observed, with MMP-9 levels positively correlated with cognitive decline in women but not in men. Overall, MMPs and their inhibitors (TIMPs) are implicated in AD pathophysiology, and their roles as biomarkers and therapeutic targets are being explored.Alzheimer's disease (AD) is a leading cause of dementia, characterized by neuronal degeneration and atrophy. Matrix metalloproteinases (MMPs), proteolytic enzymes involved in extracellular matrix remodeling, have been implicated in AD pathophysiology. This review aims to summarize recent research on the role of MMPs in AD, focusing on cell culture studies and human studies. MMPs are classified into six groups based on their structure, localization, and substrate specificity. They play crucial roles in various physiological and pathological processes, including ECM remodeling, inflammation, and signaling pathways. In AD, MMPs are upregulated in response to Aβ peptides, with MMP-9 showing potential neuroprotective effects by degrading Aβ fibrils. Cell culture studies have demonstrated that MMPs can influence APP processing and tau protein aggregation, suggesting their involvement in AD pathology. Postmortem brain tissue analysis revealed higher MMP-1, MMP-9, and MMP-3 concentrations in AD patients compared to controls, particularly in regions affected by amyloid plaques and neurofibrillary tangles. In plasma and cerebrospinal fluid (CSF), MMP-10 and MMP-9 levels were elevated in AD patients, potentially serving as biomarkers for disease progression. Sex differences were also observed, with MMP-9 levels positively correlated with cognitive decline in women but not in men. Overall, MMPs and their inhibitors (TIMPs) are implicated in AD pathophysiology, and their roles as biomarkers and therapeutic targets are being explored.