Carluccio's chief executive Neil Wickers told the Press Association that the firm will open up to 12 new outlets a year, invest in store refurbishments and revamp the menu.
"The market is more competitive than it's ever been, but we're confident that through investing we can continue to do well," he said.
"We plan to open 10 to 12 new restaurants a year over the next five years, which will create around 500 jobs annually. The investment will be in the multimillion-pound range," he said.
The cash injection comes from Carluccio's majority owner, the Jagtiani Foundation, the family office of the Landmark group.
Wickers said the Foundation, which has owned the chain since 2010, has no immediate plans to offload Carluccio's either through an IPO or a sale, although he added "at some point they will look to exit".
Carluccio's, which has 100 stores and employs 2,900 in the UK, saw pre-tax profit dip from £7.7m to £5.2m last year, according to accounts filed at Companies House.
On Brexit, the chief executive said the slump in sterling will drive up costs.
"We import a lot of ingredients from Italy, and that's all now more expensive that it was pre-Brexit. But the way to win is by giving customers better experiences, which is what we're investing in."
Alongside expansion, the investment will go towards 50 changes to the menu, with new dishes developed alongside founder Antonio Carluccio.
To celebrate the menu revamp, tens of thousands of virtual reality glasses which transport diners to the Sicilian coast are being given away.
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