The opposition says the teenager was killed when he was struck on the head by a tear-gas canister on Saturday.
State media say he suffered burns after taking part in a petrol bomb attack against security forces.
There have been frequent clashes in recent months between police and protesters, amid widespread anger at the ruling Sunnis among majority Shias.
An investigation is under way into the death of the teenager, Sayid Hashim Saeed.
On Sunday a resident in the mainly Shia village of Sitra, south of the capital Manama, told Reuters news agency: "After the funeral, many of the mourners started protesting and the police began using tear gas."
State news agency BNA quoted a police official as saying preliminary investigations suggest "the deceased was among those who took part in attacks on security forces by throwing petrol bombs".
A wave of demonstrations in February and March last year led to a crackdown in which more than 40 people died.
In November, an independent commission concluded "excessive force" had been used, and that security forces had been guilty of systematic abuse and torture.
More than 1,600 people have been arrested during the protests this year in Bahrain, which have continued sporadically since the peak of the unrest eight months ago.
Police in Bahrain have used tear gas to break up demonstrations following the funeral of a 15-year-old protester.