Almost one-quarter of self-employed people do not have superannuation, according to research by the Association of Superannuation Funds of Australia (ASFA).
ASFA's report found those who were self-employed and aged between 60 and 64 had around half the super of employees under the superannuation guarantee (SG).
Only 27 per cent of those in their 60s who were self-employed, and soon to reach retirement, were found to have more than $100,000 in super, compared to 50 per cent of employees under the SG.
Individuals with lower-value business assets were also found to be more likely to have lower super balances, or no super at all.
ASFA chief executive, Pauline Vamos, said: "Business assets such as financial, shares, or investment properties are often believed to serve as de-facto superannuation."
"However many of those who are self-employed do not have significant business or financial assets, and may struggle sustaining the standard of living they are used to when they reach retirement age," she said.
The report also found that women who were self-employed had superannuation balances that were around one-third lower than males who were self-employed.
Self-employed women aged 60 to 64 were found to have $85,000 in their retirement fund on average compared to $155,000 for a male. This figure would provide only a very modest retirement income for a female, the report said.
While 10 per cent of the workforce was self-employed, it is not compulsory for them to make super contributions.
However, there were a number of benefits self-employed people could potentially claim from the Government, such as bonus co-contributions, the association said.