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Abstract: This paper assesses the environmental impacts of producing bio-energy, bio-fuels and bio-materials from Australian sugarcane (Saccharum officinarum), and nominates the bio-production pathways offering the best environmental gains. A system-based, consequential approach was taken, which is different to past approaches that have commonly judged bio-production by comparing individual bio-products with their fossil-fuel counterparts. Possible diversified scenarios were developed, and the changes in environmental impacts from the system as a whole (per 100 t sugarcane processed) were assessed using life cycle assessment (LCA). Scenarios based on utilisation of co-products from existing sugarcane production (ethanol from molasses, and electricity and ethanol from surplus bagasse) were found to give modest reductions in non-renewable energy (NRE) use and global warming potential (GWP), and involve no or few trade-offs. Of these, ethanol and electricity from bagasse offer the best benefits. Scenarios necessitating expanded cane growing for dedicated production of ethanol and polylactide (PLA) plastics from cane juice were found to result in more substantial NRE and GWP savings, but involve the trade-offs associated with expanded agricultural production (land use, water use and potential water quality impacts). Of these, PLA production offers the better outcomes, amongst the scenarios. However, eco-efficient cane growing was found to be an equally important improvement strategy and should be implemented to enhance the benefits and mitigate some of the trade-off from bio-production. [Copyright &y& Elsevier]