Roy Hodgson announced the England squad for this summer's tournament in Brazil on Monday with many reporters and fans praising the manager for his bold approach and selection of youth.
But with Liverpool's Glen Johnson the only recognised right-back in the squad and Phil Jagielka and Gary Cahill the likely centre-half pairing, Adams told Sky Sports News he is not convinced about the ability on offer to shut out opponents on the biggest stage.
Adams is excited about the squad's attacking options but feels their defensive limitations will prevent England from challenging for the trophy.
"We've got a good keeper in Joe Hart but I don't understand why John Terry's not there and Ashley Cole's omission is a mistake," said Adams, in the UK to promote a boxing event in Bethnal Green on June 27 in aid of Refugee week for IDP (Internally displaced persons).
"But if you're going to win it I don't see this back four doing it. They've not got the quality to win it. Going forward we have a lot to offer and with Steven Gerrard keeping it organised, it's a good system.
"We will be entertaining but we're not solid enough at the back to win the tournament. It's about balance and I don't think against good opposition they'll be able to keep clean sheets.
"If we get out of the group then we may well fall short."
In conjunction with The European Azerbaijan Society and to mark World Refugee Week, Tony Adams is promoting a gala charity boxing night at York Hall, East London, on Friday 27th June between Repton and Gabala of Azerbaijan. Tickets are available at www.Repton-Gabala.eventbrite.co.uk and proceeds will go to the Mo Farah Foundation.