Up to 50 jobs could go at the Manchester Ship Canal Company, owners Peel Ports have announced.
Peel Ports employs 2,000 people around the UK
The group said staff and unions have been told of the possible redundancies and that the job cuts were part of an "ongoing operational review".
A statement said it was a move to safeguard the company's future growth.
Peel Ports employs more than 2,000 people at five ports in the UK, including the Mersey Docks and Harbour Company in Liverpool.
The planned redundancies would be made in several areas of the business, at both an operational and managerial or supervisory level.
Tom Allison, Peel Ports' chief executive, said: "The global ports sector is an increasingly competitive market and it is vital that we prepare ourselves to meet future challenges.
"The Manchester Ship Canal is absolutely pivotal to the ongoing success of Peel Ports and this exercise will play a major role in safeguarding the canal's future growth.
"We will now enter into a full consultation exercise with staff and unions to work through the implications of this plan.
"It is our intention, should these planned redundancies prove necessary, to provide enhanced redundancy payments to staff, over and above statutory levels."