Background: Hepatitis B and Hepatitis C being the most prevalent and preventable infectious disease in Sindh with prison inmates being a major risk group. Aims: To assess the knowledge, attitude and practice of this deadly debilitating disease. Study Design: Interventional Study Place and Duration of Study: It was performed in Malir Jail, Karachi, Pakistan in which 128 prison inmates participated. The research was done in three phases for the duration of 1 month. Methodology: In first phase a pre-intervention questionnaire was filled which assessed the basic knowledge regarding hepatitis, its spread and prevention. In the second phase an elaborate audiovisual presentation was given with detailed explanation to all the participants about hepatitis B and hepatitis C. In the third phase a post-intervention questionnaire was filled. Results: On assessment, the results showed that before intervention prisoners lacked basic knowledge about hepatitis and after the intervention their knowledge and awareness improved significantly with a p-value of <0.001. Conclusion: It is concluded that prison inmates of Malir jail Karachi lacked basic knowledge of hepatitis B and hepatitis C and with substantial repeated interventions this preventable infectious disease could be prevented.