The move follows "notification of an event of default under the senior credit facility, and a realisation that there were no alternatives that could be explored any further", the company said today.
Focus said its directors had sought consent from the firm's lenders to appoint Ernst & Young as the administrators. All stakeholders including staff are being informed.
Focus DIY was founded by Bill Archer in 1987, with six stores in the Midlands and the North of England. The company now has 178 stores in England, Scotland and Wales, and employs more than 3900 staff.
Private equity firm Cerberus bought Focus in 2007 for £1. It was heavily indebted at the time and Cerberus said it would pay off its £174m of debts.
Focus used to own the Wickes chain, which it bought in September 2000 before selling it to Travis Perkins in February 2005.
In 2009, the DIY and garden retail chain had to negotiate with its creditors to avoid going into administration.