Northcliffe Media said in a letter to staff that the laptop contained names, addresses, bank account details, sort code numbers of employees and freelancers working for the Daily Mail and its sister company General Trust.
The company said in a statement: "The Daily Mail and General Trust confirms that a company laptop containing certain confidential information was stolen last week.
"The password-protected computer contained limited personal information on some employees and suppliers of the Group's newspaper divisions.
"The Daily Mail and Trust Group has notified police about the incident. It has contacted all those affected and apologised for any inconvenience caused by this breach in security."
The news will be highly embarrassing to the paper, which has run many news and comment pieces on the government's data loss mistakes.
Melanie Philips, a columnist for the Daily Mail, was particularly scathing about one civil servant who lost his laptop.
"One's mouth just drops open at all this," she wrote. "Clearly, the depth of official incompetence in Britain is simply fathomless and inexhaustible. And, maybe, that's all there is to any of it."