Tajikistan is in a unique geopolitical location along the global heroin trade route, exacerbating its own opioid use disorder and HIV epidemics. With one of the highest rates of opioid use disorder in the world, and 20,000-30,000 people who inject drugs in the country, Tajikistan’s government and international actors have provided harm reduction measures for people who use drugs, like narcology centers, needle and syringe programs, and methadone maintenance therapy. No implementation science studies have been conducted in Tajikistan and the current implementation gaps in service uptake are unknown. The purpose of this paper is to determine the prevalence of harm reduction service uptake among people who use drugs in Tajikistan, and determine which factors are associated with service uptake. Methods This paper uses data from the National AIDS Registry, subset to patients who use drugs (n=11,029) and cross-sectional data from a bio-behavioral survey conducted in 2017 (n=2,390). Univariate and multivariate logistic regression were used to assess associations between study variables and probably of uptake of narcology center registration, uptake of needle and syringe programs, and registration into methadone maintenance therapy. Results Fewer than half of all people who inject drugs (42.4%) were registered with the narcology center , most people who inject drugs (88.6%) reported always having access to clean syringes, and only 5.3% of PWID had ever engaged in methadone treatment in Tajikistan. There were ethnic differences in service uptake – with ethnic Russians and Uzbeks less likely to use services than ethnic Tajiks. Men who have sex with men and people living with HIV were also more likely to access services than heterosexual or seronegative individuals. Conclusion Narcology center registration and clean needle coverage are high in Tajikistan. Methadone maintenance therapy uptake, however, is low, like in other countries in Eastern Europe and Central Asia. NGO and government initiatives that target risk groups (like LGBTQ+ people and people living with HIV) seem to have been somewhat effective at recruiting their clientele into services. Future research might focus on the “positive deviancy” of these subgroups of people who use drugs to learn how to increase service uptake generally.