The ongoing opioid epidemic is adversely affecting all Americans. Most vulnerable among us, and likely the most overlooked, are the former inmates. Prior studies suggest that opioid overdose mortality is ten times higher among former inmates than the general population. In this study, we examine the rates of opioid overdose death (ODD) among former North Carolina (NC) inmates from 2000 to 2015, compare them to the general population, and identify predictors of post-release overdose death. We linked 2000-2015 prisoner release data from the NC Department of Public Safety to 2000-2015 NC death records using soundex codes for names, birth date, and sex. Opioid overdoses were identified using ICD-10CM codes. We calculated 1-year post-release ODD rates among former inmates to compare with annual NC rates, and calculated weekly and monthly rates to identify predictors of overdose death among former inmates. From 2000-2015, 237,455 prisoners were released and 12,237 died post-release, of whom 1,104 died of an opioid overdose-related death. The opioid overdose mortality rate among former inmates increased from 53 per 100,000 person-years in 2000 to 216 per 100,000 person-years in 2014, compared to 3.3 to 9.2 per 100,000 person-years, respectively, in the general NC population. Opioid overdose mortality rates were highest during the first two weeks after release, and among former inmates who were 26-50 years of age, men, White, had three or more prior prison terms, and received long term substance abuse and mental health treatment while incarcerated. Former inmates are highly vulnerable population and need urgent prevention measures.