The decision from world football's governing body comes after German publication Bild obtained what it said was a leaked copy of the findings and on Monday published allegations it claimed were included in the document.
Garcia, a former New York attorney, was appointed by FIFA in 2012 to investigate allegations of corruption surrounding the bidding process for the World Cups in Russia and Qatar.
His report was submitted to the world governing body in September 2014, with FIFA releasing a summary two months later that cleared Russia and Qatar of wrongdoing. However, Garcia claimed at the time that version was "incomplete and erroneous".
A statement on FIFA's official website said: "For the sake of transparency, FIFA welcomes the news that this report has now been finally published."
FIFA claims that former Ethics Committee chairpersons Cornel Borbely and Hans-Joachim Eckert had refused to publish the full report, despite numerous requests from president Gianni Infantino.
Outgoing chairman of the adjudicatory chamber Eckert said in November 2014 that his department "did not find any violations or breaches of the relevant rules and regulations" regarding Qatar's World Cup bid.
Maria Claudia Rojas and Vassilios Skouris – who were elected in May to replace Borbely and Eckert in the investigatory chamber and the adjudicatory chamber respectively – have now taken the decision to release the investigation in its entirety.
FIFA's statement read: "This had been called for on numerous occasions by FIFA president Gianni Infantino in the past and also supported by the FIFA Council since its meeting in Mexico City in May 2016.
"Despite these regular requests, it is worth noting that the former chairpersons of the Ethics Committee, Cornel Borbely and Hans-Joachim Eckert, had always refused to publish it.
"The Ethics Committee will meet in its full composition under the new chairpersons for the first time next week, and it was already planned to use this opportunity to discuss the publication of the report.
"However, as the document has been illegally leaked to a German newspaper, the new chairpersons have requested the immediate publication of the full report (including the reports on the Russian and US bid teams, which were conducted by Mr Borbely alone) in order to avoid the dissemination of any misleading information."