The Westpac-Melbourne Institute survey of consumer sentiment fell 3.9% this month, following a decline of 1.1% in November.
The Westpac consumer confidence survey is based on responses from 1,200 adults aged 18 and over from across Australia. The survey is usually administered in the first four days of each month.
Underlying consumer confidence took a hit after the economy contracted in the third quarter for the first time since 2011. Gross domestic product (GDP) shrank at a seasonally adjusted 0.5% in the three months through September, following an upwardly revised 0.6% gain the previous quarter, government data showed last week.