The activities had a turnover of close to €100m (£92m) in 2016, mainly in Kuwait, Congo and Panama
The transaction would see the integration of 110 Saipem employees into Eiffage.
Eiffage already carries out maritime works in France and Belgium and the acquisition is intended to strengthen its international capabilities in the sector. It is seen as a step in Eiffage move towards greater international deployment on specialist activities and would also enable synergies on major and projects.
The transaction is subject to the customary legal, regulatory and financial approvals; it is expected to be finalised by the end of this year.