Sheikh Salman would "only further tarnish the organisation's image" if he became FIFA president, according to pressure group Human Rights Watch.
International non-governmental organisation Human Rights Watch has strongly condemned Sheikh Salman bin Ibrahim al-Khalifa's candidacy to become the next president of FIFA.
The Bahraini formally entered the race to replace outgoing president Sepp Blatter ahead of Monday's deadline for submissions.
Sheikh Salman previously backed Michel Platini's bid but the UEFA president remains provisionally suspended from FIFA for 90 days along with Blatter in relation to an alleged "disloyal payment" that has thrown world football's governing body into a state of flux.
As a member of Bahrain's royal family that has been regularly criticised by human rights groups for the regime's oppression of pro-democratic demonstrations and alleged use of torture, Human Rights Watch warned that Sheikh Salman cannot be viewed as the unifying figure to steer FIFA through its latest troubled period.
"The election of a member of Bahrain's royal family to the FIFA presidency will only further tarnish the organisation's image," read a statement given by Nicholas McGeehan, the Bahrain, Qatar and United Arab Emirates researcher at Human Rights Watch.
"This is far more serious than bungs and brown envelopes. Bahrain's ruling Al Khalifa family has presided over a bloody crackdown and its security forces have committed terrible abuses against anyone who criticises their rule.
"FIFA members should look long and hard at the Al Khalifas' use of torture and allegations that Sheikh Salman failed to protect footballers from abuses, and ask themselves if this is a family they want to represent them at the highest level."
Sheikh Salman joins former FIFA executive Jerome Champagne, UEFA general secretary Gianni Infantino and Liberia Football Association chief Musa Bility as an official candidate to succeed Blatter.
The poll is scheduled to take place on February 26.