We investigated social network factors associated with participation in overdose prevention training among injection drug users (IDUs). From 2008 to 2010, 106 IDUs who had witnessed an overdose in the past year from two syringe exchange programs in Los Angeles provided data on overdose prevention training status (trained vs. untrained), social networks, history of overdose, and demographics. In multivariate logistic regression, naming at least one network member who had been trained in overdose prevention was significantly associated with being trained (Adjusted Odds Ratio 3.25, 95% Confidence Interval 1.09, 9.68). Using social network approaches may help increase training participation. Limitations are noted.