Aim: This study aimed to assess the prevalence of substance abuse in individuals diagnosed with schizophrenia and explore the relationship between demographic characteristics, substance abuse patterns, and the severity of schizophrenia symptoms.Materials and Methods: A cross-sectional study was conducted with 130 participants, aged 18-65 years, diagnosed with schizophrenia at a tertiary care hospital. Demographic and clinical data were collected through structured interviews and medical records. Substance abuse was assessed using the Substance Use Disorder Identification Test (SUDIT) and Drug Abuse Screening Test (DAST), while schizophrenia severity was evaluated using the Positive and Negative Syndrome Scale (PANSS). Statistical analyses included Chi-square tests and logistic regression.Results: The prevalence of substance abuse was 42.31%, with alcohol (23.08%) and marijuana (19.23%) being the most commonly abused substances. Males showed a higher prevalence of substance abuse (47.06%) compared to females (33.33%). The 18-30 years age group had the highest prevalence (50%), with a significant association between younger age and substance abuse (p = 0.002). Moderate schizophrenia symptoms were most strongly associated with substance abuse (p = 0.002).Conclusion: Substance abuse is prevalent among individuals with schizophrenia, with alcohol and marijuana being the most commonly abused substances. Younger males and those with moderate schizophrenia symptoms are particularly vulnerable to substance abuse. These findings underscore the importance of tailored interventions to address substance use in this population, with a focus on younger patients and those experiencing moderate symptom severity.