Utilities company said that loss was due to goodwill written off when Morrison was bought last month.
Utilities company AWG lost £56.4m when it sold Morrison Construction and Morrison Projects Investments two months ago.
The company attributed the loss on disposal to £93.1m of goodwill that was written off when it bought Morrison in 2000.
In March, AWG sold Morrison Construction and Morrison Projects and Investments to Galliford Try for £42m.
AWG kept Morrison Support Services and says its focus is now on developing the support services business.
In February, AWG settled its long-standing legal dispute with Sir Fraser Morrison. The company claimed Sir Fraser had inflated the value of the Morrison company, which it originally bought for £263m. AWG was seeking £130m, however the settlement was made out of court and the terms remain confidential.
AWG's interim results to the year ended 31 March showed the company made a pre-tax profit of £108.8m and had a turnover of £1,552.2m.