Background: There has been a recent increase in the number of heterosexually acquired HIV infections among non-Aboriginal people in Western Australia (WA), which has not been reported in other Australian jurisdictions. This report describes the epidemiological features of this increase. Methods: A descriptive analysis was conducted of newly diagnosed HIV infections among non-Aboriginal WA residents notified to the Department of Health from 2002 to 2006. Analysis outcomes included demographics, exposure categories, and place of HIV acquisition. Results: From 2002 to 2006, 258 new HIV diagnoses were notified among non-Aboriginal WA residents. Over this period, the number of notifications increased from 41 cases in 2002 (2.2 cases/100 000 population) to 66 cases in 2006 (3.4 cases/100 000 population). Overall, 107 (42%) of the cases were heterosexually acquired, and the annual number increased threefold from 2002 to 2006 (12 to 36 cases, respectively). Of these cases, 64 (60%) were male and 43 (40%) were female. The majority (89%) of male cases acquired HIV overseas, mostly in countries other than their region of birth; South-east Asia was the most common place of acquisition reported. Over half (56%) of the female cases acquired HIV overseas, mainly in their region of birth (83%), and sub-Saharan Africa was the most common place of acquisition. Conclusion: There has been a recent increase in heterosexually acquired HIV infections among male and female WA residents, many of whom reported acquiring HIV overseas. Safe sex campaigns in WA should continue to reinforce safe sex messages among people travelling overseas.