Background: There is high prevalence of HIV among Injecting Drug Users (IDUs) in Vietnam with a national level prevalence just under 20%. Both drug and sex related risk behaviors are widespread among IDUs. The objective of this review is to analyze HIV risk behaviors and identify the epidemiologic implications. Methods: Major databases were searched during November-December, 2011. Finally, 55 peer-reviewed articles were identified and reviewed to focus on risk behaviors of IDUs, Female Sex Workers (FSW) and drug policy and harm reduction program related issues. Results: Young injectors are involved in risk behaviors that include frequent sexual connections with FSWs. Our review found that young IDU subgroups (=30 years) are engaged in high risk behaviors and have limited access to harm reduction services. Sexual risk factors associated with drug injecting FSWs may become the catalyst for a future heterosexual transmission if the prevalence rises further. Future research should focus on young injectors to investigate the structure and characteristics of networks to help guide harm reduction programs, including IDU subgroups. Conclusion: Vietnam has still a window of opportunity to learn from the experience of neighboring countries and, after modification, to incorporate preventative services suited to the needs of young injectors, into existing programs.