While the content of the service cannot yet be published, it will be hosted hosted by Air Chief Marshal Sir Joe French KCB CBE, who is also vice chairman of the Commonwealth War Graves COmmission.
The service will be led by the Chaplain General to Her Majesty's Land Forces, The Reverend Dr David Coulter QHC.
Up to 600 guests will attend the service included diplomatic and military representatives of nations that were involved in the campaign and descendants of some of those who were involved in the Gallipoli Campaign one hundred years ago.
Among the attendees are Prime Minister John Key and his Australian counterpart Tony Abbott and their wives.
The Helles Memorial was built in 1924 and serves two functions.
Firstly, it is the Commonwealth battle memorial for the whole Gallipoli campaign and secondly, it is a place of commemoration for British and Commonwealth servicemen who died there and have no known grave.
There are also memorial panels for those buried at sea.
There are more than 21,000 names on the memorial, designed by John Burnet.
AMong the names are five Victoria Cross recipients, five soldiers who played rugby at an international level before they were killed and a first-class cricketer.
Cape Helles was an integral part of the Gallipoli campaign. On 25 April 1915, as the Anzacs stormed the beach near Ari Burnu, British forces were launching an amphibious attack at Cape Helles.