The Qatar-headquartered news outlet, which has been broadcasting in the UK since 2006, has handed over what is understood to be a retained brief following a pitch process last year.
The move comes after the end of a three-year relationship of rolling project work with Burson-Marsteller.
As part of the battle to compete in a crowded news market, in November Al Jazeera became the first channel outside of the UK’s public service broadcasters to launch in HD format on Freeview.
The move came a few months after reports it had launched a major drive on commissioning UK factual and current affairs programmes.
The head of media and PR at Al Jazeera Media Network, Osama Saeed, said: "Al Jazeera English is already the most-watched international news and current affairs channel in the UK. In today’s interconnected global village, there’s a huge need and appetite for our news and programmes. We want to continue increasing our audience.
"We found Edelman was the ideal partner to help us achieve this, with its knowledge of the British media landscape, creative approach to communications and experienced talented team."
Burson-Marsteller was initially hired by the company in 2011 in an effort to help raise awareness of its news output, with a spokesman confirming the relationship had ended late last year.