They include the Mir, from Russia, which is the tallest ship to have confirmed so far. In Russian, Mir means 'peace'.
Nearly 40 ships are now confirmed for the event between Wednesday 11 and Saturday 14 July. The first ships are expected to be entering the River Wear on Tuesday 10 July.
Mir will be moored at Corporation Quay on the south bank of the River Wear opposite the National Glass Centre. She is 109m (350ft) long and her main mast is 52m (170ft) tall.
Councillor John Kelly, the City Council's Portfolio Holder for Public Health, Wellness and Culture, said: "I understand Mir is big, very big, and she is very tall. She will be getting a prime berth at Corporation Quay. I know her 200 permanent crew and trainees will be made to feel extremely welcome and plenty of activities and events are being lined-up for all our visitors.
"Her arrival and stay in our city are another highlight for an event that is shaping up to be very spectacular."
Also now confirmed for July are:
* The Indian Navy's Tarangini, which joins Urania, as the second military-operated ship in the fleet. She is a 53m (173ft) Class A Barquentine ship;
* Jolie Brise is a Class B ship with distinctive red sails and black wooden hull. Owned and operated by Dauntsey School in Wiltshire;
* Aries is a privately owned Class D vessel that will make up part of the 'small ships community', which is an integral part of any Tall Ships event.
One of the highlights will be the Parade of Sail on the afternoon of Saturday 14 of July. The fleet is due to begin undocking at approximately 2pm to parade between the Wear's historic piers in the two hours before high tide at 5.15pm.
The parade bears north along the coast until level with Souter Point, then turns back south to a start line which is four miles east from the piers.
Cllr Kelly added: "The events programme is taking shape, and looking more and more ship-shape as more ships and contributors are coming on-board and I'm confident we can expect some Airshow sized crowds.
"The city's Tall Ships team are working hard behind the scenes with vessel operators to attract a magnificent fleet and this is paying dividends as 24 of the fleet confirmed so far are the larger Class A or Bs."
Ships will be berthed in Hudson Dock and at berths on the north and south banks of the river.
More information on the fleet and the event is at www.tallshipssunderland.com
FOUR more tall ships have signed up for this year's Tall Ships Event in Sunderland.