The ACE wrote to Constructionline last week saying the group would review its support next year because of concerns that not enough clients have signed up.
A recent survey of ACE members found that 75% of those polled thought the service from Constructionline was poor, 73% said they never got work as a result of registering with the service and 36% thought the ACE should withdraw its support of the scheme.
The survey concluded: "Firms only retain their Constructionline membership because they feel obliged to, in order to win public sector work. The attitude towards Constructionline is one of resignation and hostility."
In his letter to Constructionline, ACE chief executive Nicholas Bennett said the association still supported the vetting service in principle but had concerns about its effectiveness and efficiency.
Bennett said: "Should a further survey of our members show no substantial improvement, the association will decide whether to continue to recommend membership to Constructionline."
The attitude to Constructionline is one of resignation and hostility
ACE survey of members
Bennett added that the association wanted to continue work with Constructionline, which is jointly run by the government and private firm Capita, to create key performance indicators to improve the service to its members.
Constructionline this month itself launched a survey of services among users, which is being carried out by the University of Salford.
Constructionline said in a statement: "We are obviously keen to look at any specific service issues that are affecting ACE members."
The warning by the ACE, which has also been made known to the construction unit at the DTI, comes in the face of government figures that show Constructionline has increased membership among clients, contractors and consultants.
The DTI figures, for the year to June, show that client members have risen 18% to 1432. The number of contractors and consultants have gone up 4% to 10,501.