The retailer said that the chain had been sold to a US investment group consisting of Angelo, Gordon & Co, MTN Capital Partners and Bruce Weitz for $61.5m (£35.4m) in cash.
The sale, which is expected to be completed by the end of April, will come as no surprise to analysts who have predicted a sale of the chain for many years.
In 1999, M&S tried to sell Kings but changed its mind after failing to “achieve the price that reflected the value of the business”.
Ian Dyson, group finance officer for M&S, said: “The disposal of Kings is the last part of our programme to refocus M&S.”
He added: “Kings is a strong brand with a committed workforce, but it doesn't fit within our core business. We wish them well under their new ownership.”
M&S said that for the year to April 2, 2005, turnover of Kings was $405.9m (£219.8m) and operating profit was $7.9m (£4.3m).