Griffiths will be part of the global firm's international capital markets practice, based in London.
He will work across a range of briefs in aerospace, defence, transport, energy and natural resources, and be involved in new business development.
Tim Linacre, senior partner, Capital Markets, said Griffiths had "a great reputation in UK industry as an enthusiastic supporter of British know-how and technology".
Before the Mail, Griffiths worked as assistant editor and head of news at City AM, and prior to this worked at The Herald, Press Association and BusinessAM.
