The scheme, which covers 1.7km between Jacob's Ladder and the War Memorial, will be constructed in two phases from August to November and then April to July 2012.
Mark Gardner, operations director at VolkerStevin, said: "Our team is currently setting up our site offices and finalising the detailed design. The major works will start at the end of August when the large rocks for the rock groynes arrive on barges.
"This is obviously a very sensitive area to be working in, and as with all coastal protection schemes we have undertaken, we are very aware of our environment and the controls we must put in place to ensure we have the minimum impact possible, whilst providing the maximum benefits."
Councillor Smith of Suffolk Coastal District Council, said: "These works are vital to the future of Felixstowe and I cannot wait to see them completed in summer 2012. It will mean some short-term disruption but given the state of the existing defences, we have to press ahead with the work as quickly as possible."
The work is being funded by the government via the Environment Agency and will help with the long term management of the beach as well as increasing public access to the coastline.