Rihanna claims she was "effectively bankrupt" in 2009.
The Only Girl in the World hitmaker blames her accountants' poor decision making for her fortune dwindling away from US$11 million (NZ$13m) in cash at the beginning of the year to $2 million (NZ$2.4m) several months later.
In documents filed in her gross mismanagement case against the accountancy firm, Berdon LLP, Rihanna claims they gave her the go-ahead to buy a house priced between $7 and $7.5 million, which she did - and later sold for a $2 million loss.
To further add to her financial woes that year, the singer's expenses "doubled", TMZ reports.
In the lawsuit, Rihanna also claimed her 2009 Last Girl on Earth tour was losing money but she was never warned of this by the accountants.
Berdon previously claimed Rihanna's own "financial action or inaction" or those of people working for her caused her to lose money, not their decision-making.
They also dismissed the Diamonds star's previous objection she paid an "above-average" commission of 22 per cent as something she had signed off on herself.
The 25-year-old star is now worth an estimated $43 million.
- Bang! Showbiz