The Scottish Finance Secretary hopes to raise an extra £30m by charging large high street shops and out of town shopping centres up to £320 000 a year on top of their existing business rates.
Business rates are paid to councils, but for any property valued at more than £2.1m, the Scottish Government would take a supplement of 15p in the pound under the plan. It is estimated that B&Q would pay an extra £2m year under the tax.
Critics say it will undermine the success of Glasgow's Style Mile and the ability of Scotland's retail sector to attract top traders north of the border.
But backers say the additional money will be used to help councils improve services for businesses.