This paper analyses what influences professionals’ beliefs on agricultural genetic engineering. A telephone survey was conducted in 2004 on Australian public agricultural professionals. Using an ordered probit regression, some of the significant key influences on overall beliefs were: age; research relevance; ethnicity; farm background; information and occupational effects; attitudes towards the current sustainability of conventional agriculture; attitudes towards agricultural research issues; and attitudes towards the individual aspects of genetic engineering. Somewhat surprisingly, subjective knowledge of genetic engineering was not a significant factor in influencing overall beliefs, although it did play a positive influence on some individual beliefs (such as the technology’s profitability benefits and that there is no need for more long-term research before further general release of genetically engineered products). However, more research on the links between actual knowledge and acceptance are needed before any definitive conclusions can be drawn.