The Welshman, 31, led Team Sky in the Giro in May, but his hopes were ended when a police motorbike caused a crash on the Blockhaus climb on stage nine.
Thomas was forced to withdraw from the race, but he is fit to support Chris Froome's bid for a fourth Tour title.
The Tour, which begins in Dusseldorf in Germany, runs from 1-23 July.
Spaniard Mikel Landa, who was also involved in the crash at the Giro but recovered to finish 17th, is also in the squad.
Britons Ian Stannard and Peter Kennaugh are notable omissions, along with Wout Poels.
Dutchman Poels, who played a major role in Froome's victory 12 months ago, suffered a significant knee injury in February and only returned to race at the Route du Sud earlier this month.
Stannard and Kennaugh were both in the Sky team in the traditional Tour warm-up race, the Criterium du Dauphine, but have been overlooked in the final selection.
That means there are three Britons in the squad, with Froome and Thomas joined by road captain Luke Rowe.
Froome is aiming to win the Tour for a third straight year, and fourth overall, following victories in 2013, 2015 and 2016.
"We're ready as a team and I can't wait for the Tour to start now," said the 32-year-old. "Honestly, I just love it. It's a feeling that you don't get from any other race."
Team: Chris Froome, Sergio Henao, Vasil Kiryienka, Christian Knees, Michal Kwiatkowski, Mikel Landa, Mikel Nieve, Luke Rowe, Geraint Thomas.

His name is most closely associated with nationalist Egyptian President Gamal Abdel Nasser in the 1960s.
Mr Heikal was the editor of Egypt's state-owned newspaper, Al-Ahram, during that time, articulating the Nasserist ideology of "Arab socialism".
He also served as information minister and briefly as foreign minister.
Following Nasser's death in 1970, Mr Heikal was sidelined by his successor Anwar al-Sadat. And in 1981 he was jailed along with hundreds of government critics.
He was released by Hosni Mubarak after Sadat's assassination by Islamist militants later that year, but was kept at arm's length by the president throughout his 29 years in office.
But Mr Heikal remained for decades one of the most authoritative commentators on Egypt and the Arab world - as well as a historian of the tumultuous events of the Nasser area.
Announcing Mr Heikal's death on Wednesday, Al-Ahram said he been ill for three weeks, and had suffered fluid on the lungs and kidney failure.
President Abdul Fattah al-Sisi paid tribute to Mr Heikal, calling him a "journalistic icon", while the cabinet said he had "massively participated in enriching intellectual life with his books, articles, political and historical studies", Egypt's ON TV Live reported.

The incident was reported at 13:45 BST on Saturday.
The Air Ambulance Northern Ireland airlifted the boy to the Royal Belfast Hospital for Sick Children where he is in a stable condition.
The callout was the first mission for the helicopter and its crew.
The air ambulance team is currently working through final preparations including training and familiarisation flights ahead of an official media launch of the service planned for early August.
However as a result of the serious nature of the incident, the aircraft was tasked to bring the Helicopter Emergency Medical Service (HEMS) doctor and paramedic to the scene.
Glenn O'Rorke, the operational lead for HEMS, said that the service will provide a doctor-paramedic team, for the whole of Northern Ireland, which will provide rapid interventions at the scene of where people have been injured before transferring patients to the appropriate hospital.
"It will make a huge difference to patients' lives and their outcome, it will improve their quality of life after injury because we will be there in a very short period of time," he said.
The campaign for the HEMS was begun by the late Dr John Hinds.
Northern Ireland was previously the only part in the UK without such a service.
Geraint Thomas has recovered from the injuries he sustained at the Giro d'Italia to be named in Team Sky's squad for next month's Tour de France.
[NEXT_CONCEPT]
One of the most famous and influential journalists in the Arab world, the Egyptian Mohamed Hassanein Heikal, has died in Cairo at the age of 92.
[NEXT_CONCEPT]
An 11-year-old boy has been seriously injured following an incident involving a tractor in the Castlewellan area of County Down.