Naloxone distribution to injecting drug users (IDUs) for peer administration is a suggested strategy to prevent fatal heroin overdose. The aim of this study was to explore attitudes of IDUs to administration of naloxone to others after heroin overdose, and preferences for method of administration. A sample of 99 IDUs (median age 35 years, 72% male) recruited from needle and syringe programs in Melbourne were administered a questionnaire. Data collected included demographics, attitudes to naloxone distribution, and preferences for method of administration. The primary study outcomes were attitudes of IDUs to use of naloxone for peer administration (categorized on a five-point scale ranging from "very good idea" to "very bad idea") and preferred mode of administration (intravenous, intramuscular, and intranasal). The majority of the sample reported positive attitudes toward naloxone distribution (good to very good idea: 89%) and 92% said they were willing to participate in a related training program. Some participants raised concerns about peer administration including the competence of IDUs to administer naloxone in an emergency, victim response on wakening and legal implications. Most (74%) preferred intranasal administration in comparison to other administration methods (21%). There was no association with age, sex, or heroin practice. There appears to be strong support among Australian IDU for naloxone distribution to peers. Intranasal spray is the preferred route of administration.