The decision, Health Canada said, came after it had completed an inspection of the facility in Baltimore, Maryland, along with the European Medicines Agency and South African Health Products Regulatory Authority.
The beleaguered facility has been under regulatory scrutiny since a manufacturing error earlier this year ruined millions of doses of J&J's COVID-19 vaccine.
Canada in June said it would not accept any doses made at the plant until it completed its own on-site inspection.
The three regulators found the facility to be compliant with good manufacturing practices, Health Canada said on Wednesday.
The U.S. Food and Drug Administration in April halted operations at the facility after J&J's vaccine was found to be contaminated with material from AstraZeneca's COVID-19 shots, which were also being manufactured there at the time.
The FDA's inspection had turned up a long list of problems, including peeling paint, shoddy cleanups, and poorly-trained staff.
Use of many doses of the J&J vaccine made at the Emergent facility is still not cleared by the FDA, although the agency has since cleared uses of batches manufactured prior to the production halt.
The FDA, Emergent, and J&J did not immediately respond to Reuters' request for comment.
Earlier on Wednesday, Canada said it had granted full approval to the J&J vaccine.
(Reporting by Manas Mishra in Bengaluru; Editing by Sriraj Kalluvila)