BACKGROUND: Harm reduction, when applied to drug use, prioritizes improving patient-centered health outcomes and reducing drug-related harm. In order for harm reduction strategies to be adopted by people who inject drugs (PWID), they need to be promoted, accessible, and accepted in that population and the community-at-large. While PWID face stigma at multiple levels, less is known about how stigma influences uptake and acceptance of harm reduction services and strategies among PWID. OBJECTIVE: We aim to characterize the stigmatizing experiences PWID have had related to harm reduction and the role of stigma in influencing their acceptance and adoption of harm reduction services and strategies. DESIGN: A qualitative study using in-person, semi-structured interviews. PARTICIPANTS: We recruited hospitalized participants, age 18 and over, with a history of injection drug use. APPROACH: We developed an interview guide asking about various aspects of stigma and participants' experiences with naloxone, syringe service programs, fentanyl test strips, HIV and hepatitis C testing, and any other harm reduction strategies. Key themes were generated using a thematic analysis. We reached thematic saturation at 16 participants. KEY RESULTS: PWID reported multi-level stigma related to harm reduction from themselves, the public, the healthcare system, and the legal and carceral systems. Themes were grouped into four main categories: internalized, interpersonal, intervention, and structural stigma. Stigma across all of these domains negatively impacted the ability of PWID to access harm reduction resources. Positive, non-stigmatizing experiences from others, such as syringe service programs and peer navigators, countered historically negative experiences and promoted greater education and comfort about using harm reduction resources among PWID. CONCLUSIONS: To expand the reach of harm reduction services, it is critical to develop interventions that can reduce the stigma against PWID and harm reduction.