OBJECTIVE: To investigate risk behaviours associated with the transmission of blood borne viruses (BBVs) and sexually transmitted infections (STIs) among transient rural workers in Victoria. DESIGN: Cross-sectional study using a convenience sampling frame. SETTING: Between June and August 2006, 89 participants were recruited from sites located in three rural centres in Victoria's Loddon and Mallee regions. Data were collected using a short questionnaire that asked about history of transient work, sexual history, condom use, alcohol and illicit drug use, and BBV history and testing. Finger-prick blood samples were collected in order to determine prevalence of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) exposure. RESULTS: Eighty-nine individuals completed a questionnaire, and 85 (96%) provided a finger-prick blood sample for antibody testing. Twenty-seven participants (30%) were consuming alcohol at levels risky to health. Thirty per cent of participants with new partners reported infrequent condom use. Illicit drug use (mainly marijuana) was widespread with more than 46% of the sample reporting recent use of illicit drugs. An HCV exposure prevalence of 2.4% was measured; no samples tested reactive for HIV antibodies. CONCLUSIONS: Compared with nationally representative data, our study sample reported high rates of alcohol consumption at levels risky to health, illicit drug use and infrequent use of condoms. These results suggest that transient workers and their contacts would benefit from the targeted provision of harm-reduction services, with a particular focus on sexual behaviour and alcohol and drug use.