Background: The success of human population biobanks are dependent on the publics' willingness to participate. This research aimed to determine those factors important in determining the public's intention to donate a biological sample to a publicly funded biobank, and allow that sample to be linked with medical records. Methods: A national sample of 1000 Australians was surveyed via telephonic interviews. Questions included the reported likelihood that respondents would participate in biobank research, ratings of trust in biobanks, beliefs that biobank research will lead to improved health care and general ratings of comfort with blood taking and DNA analysis. Results: The sample reported a high level of trust in university biobanks, a strong belief that biobank research will lead to improved health care and a strong willingness to participate in biobank research. Using structural equation modelling, trust in the biobank was found to be the most important determinant of intention to participate in biobank research, followed by general comfort with blood taking and DNA analysis, belief in health-care benefits and higher education. Gender, age, parental status and experience of genetic conditions were not significantly associated with intention to participate. Conclusions: Australians are generally willing to participate in biobank research, and this is strongly determined by trust. While benefit beliefs and comfort with research are also relevant, higher trust was associated with intention regardless of these factors, suggesting reasons other than concern for improved health care are important in determining the publics' willingness to participate in biobank research.