It is particularly concerned about slow broadband penetration rates in newer member states like Bulgaria, which has only a 5.7% rate compared to Denmark's 37.2%.
In a report, lack of competition and regulatory weaknesses are cited by the commission as the main obstacles to broadband growth.
The commission plans to address these shortcomings in proposals to reform the EU's telecoms legislation on 13 November.
"Broadband growth remains strong with the top EU countries now world leaders in broadband penetration," said EU telecoms commissioner Viviane Reding.
"However, it is unacceptable that the gap between the strongest and weakest performers in Europe is growing. Europe must act now to get its broadband house in order. I will make specific proposals on this as part of our package of reforms for the EU Telecom Rules on 13 November."
The commission may also consider enforced broadband price cuts to stimulate demand. BT is currently offering UK broadband subscribers who are out of contract price cuts on basic packages.