Almost £600,000 which was transferred to a Hong Kong account before being moved to a bank in China came from the proceeds of crime, a court heard.
Birmingham Crown Court heard how the money was transferred to the account of Bo Li, 39, of Stratford Road, Shirley, West Midlands, over just two years.
The court also heard how Bo Li also had a hand in buying four properties.
Bo Li and three other defendants deny a total of 24 charges relating to money laundering.
Ex-company director Anthony Whale, 34, of Holbeache Road, Kingswinford, near Dudley, and Yaqiong Zhao and Ke Qu, both 25 and of Churchfield Street, Dudley, were arrested in October 2006 after a bank alerted police to a "suspicious" deposit of £43,800 in cash.
The court heard Bo Li then flew to Hong Kong and closed down her account, which had just less than £600,000 in it.
She was also alleged to have cleared her accounts in the UK, transferring cash to the Bank of China.
David Matthew, prosecuting, said he did not intend to present evidence of where the money came from.
However, he said the explanations given by Bo Li did not add up and that it must have been "plainly illegal money".
The trial continues.