Abstract Background: Tattooing is among identified risk factor for blood-borne diseases. Objective: This study aims to determine the prevalence of tattooing during lifetime and in prisons and its related factors among Iranian prisoners. Methods: This is a cross-sectional study. The required data was obtained from hepatitis B and C surveillance surveys in prisons in 2015-2016 that was collected through face-to-face interview. 12,800 prisoners were selected by multi-stage random sampling from 55 prisons of 19 provinces in Iran. Weighted prevalence and associated factors (using Chi-Square test and multivariate logistic regression) were determined by Stata/SE 14.0 survey package. Results: Out of 12,800 prisioners, 11,988 participated in the study (93.6% participation rate). The prevalence of tattooing in lifetime and in prisons was 44.7% and 31.1% respectively. The prevalence of tattooing during lifetime was significantly associated with age < 35 years, being single, illiteracy, history of imprisonment, drug use, piercing during lifetime, extramarital sex and history of STI; the prevalence of tattooing in prison had a significant association with history of imprisonment, drug use, piercing in prison, and history of extramarital sex (p < 0.05). Study limitations: Information and selection bias was one of the study limitations. Conclusion: The results of this study showed that the prevalence of tattooing during lifetime and in prison among prisoners was significantly high especially in high-risk groups such as drug users and sexually active subjects. Given the role of tattooing, drug injection and sex in the transmission of blood-borne diseases, harm reduction programs are recommended to reduce these high-risk behaviors in prisons.