We extended a recent model of climate change risk perception (van der Linden, 2015) to predict the risk perception of Australians and their willingness to engage in mitigation behaviours (N = 921). Affect, mitigation response inefficacy, and descriptive norms were the most important predictors of risk perception, highlighting the influence of affective, cognitive, and socio-cultural factors. Affect and mitigation response inefficacy were also important predictors of behavioural willingness, but socio-cultural influences (free-market ideology, prescriptive norms, and biospheric values) played a relatively larger role in explaining the variance of behavioural willingness. Structural equation modelling provided further evidence that risk perception and behavioural willingness are separable constructs, as some factors in the model had direct effects on willingness independent of risk perception. We discuss the need for future research to develop a comprehensive model of behavioural willingness, and the need for public communication to combat mitigation response inefficacy.