Under the proposal, Pegler, which was acquired by Aalberts in 2005, could have its production relocated to other facilities.
Aalberts said on Thursday that a consultation was under way and all employees at the Pegler site in St Catherine's Avenue had been informed.
The firm said no final decision had been made and confirmed the proposed move would not affect its distribution centre in Manvers.
While Aalberts did not confirm how many employees would be affected by the announcement, it said it was providing support "at this unsettling time".
John Dillon, General Manager for Aalberts Integrated Piping Systems UK, said the company had "begun a consultation regarding a proposal to cease manufacturing operations at the Doncaster site, which could lead to the relocation of production to other Aalberts facilities".
He added: “While no final decisions have been made, we want to be transparent and we must look at ways to remain competitive in global markets."
Sales would continue to be UK-based, as would the company's business support functions such as finance, IT and HR, Mr Dillon said.
According to the Aalberts website, Pegler is one of the world's leading manufacturers of advanced plumbing, heating and engineering products.
Pegler was first established in the 1890s and at the time of its acquisition by Aalberts in 2005, it employed over 500 people.
