Background: Sudden cardiac death (SCD) in young adults is a devastating and unexpected event, often with no prior symptoms. Although traditionally associated with older populations, SCD among individuals aged 18–40 years is increasingly reported. Identifying risk factors is critical for screening, prevention, and timely intervention. Aim: To analyze the major clinical, lifestyle, genetic, and structural risk factors associated with sudden cardiac death in young adults. Methods: A retrospective observational study was conducted from January 2019 to December 2023 in a tertiary care hospital. 120 documented cases of sudden cardiac death (aged 18–40 years) were reviewed and compared with 120 matched controls who survived acute cardiac events. Data included clinical history, ECG findings, family history, echocardiographic patterns, lipid profiles, substance use, and physical activity levels. Statistical analysis was done using SPSS (v25). Results: Major risk factors found were: hypertrophic cardiomyopathy (HCM) (24%), congenital long QT syndrome (10%), myocarditis (9%), previous unnoticed arrhythmia (17%), smoking and alcohol abuse (42%), drug use (9%), family history of SCD (14%), and sedentary lifestyle (38%). ECG abnormalities (especially QT prolongation and ventricular arrhythmias) were significantly more prevalent in SCD cases (p < 0.001). Males had a 1.8 times higher risk compared to females. Lack of awareness, poor screening programs, and misdiagnosis were major contributing factors. Conclusion: Structural heart disease, undiagnosed arrhythmias, genetic predisposition, and lifestyle-related risks significantly contribute to sudden cardiac death in young adults. Early screening with ECG and echocardiography, family history evaluation, lifestyle modification, and public awareness campaigns are urgently needed to minimize preventable deaths.