The closures will affect some 120 employees, but the celebrity chef hopes to offer them alternative roles in other parts of his restaurant empire.
The six restaurants are all scheduled to close in the first quarter of 2017.
The Group has been stung by the collapse in the pound, which has ramped up the cost of buying ingredients from Italy.
According to accounts, revenue at Jamie’s Italian rose by almost 9 per cent to £116.1 million in 2015, although profits fell from £3.8m to £2.3m. There are 42 Jamie’s Italian outlets in the UK and 28 overseas.
The Group will now focus on the “core Jamie’s Italian estate”, to launch another 22 Jamie’s Italian restaurants and develop its newly acquired Australian restaurants in 2017.