<p><b>OBJECTIVE: </b>Hispanics/Latinos have the highest risks for metabolic syndrome (MetS) in the U.S. and are also at increased risk for Alzheimer disease. In this study, we examined associations among neurocognitive function, MetS, and inflammation among diverse middle-aged and older Hispanics/Latinos.</p><p><b>RESEARCH DESIGN AND METHODS: </b>Cross-sectional data (2008-2011) from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) were analyzed to examine associations between neurocognition and MetS among diverse Hispanics/Latinos ( = 9,136; aged 45-74 years).</p><p><b>RESULTS: </b>MetS status was associated with lower global neurocognition, mental status, verbal learning and memory, verbal fluency, and executive function. Age significantly modified the associations between MetS and learning and memory measures. Significant associations between MetS and neurocognition were observed among middle-aged Hispanics/Latinos, and all associations remained robust to additional covariates adjustment.</p><p><b>CONCLUSIONS: </b>We found that MetS was associated with lower neurocognitive function, particularly in midlife. Our findings support and extend current hypotheses that midlife may be a particularly vulnerable developmental period for unhealthy neurocognitive aging.</p>