Just days before the pageant is due to start on the resort island of Bali, the demonstrators called on authorities to cancel it and brandished banners reading "Miss World Go to Hell".
They also waved banners reading "Boycott Miss World sponsors" as they marched in central Jakarta to the offices of media group MNC, which will broadcast the show.
"The contest will invite danger and vice. Muslims must never let this happen," one protester shouted to the crowd, who responded with chants of "God is great".
"We call for war against Miss World. We urge the Indonesian government to call off the Miss World event," added Irfan Awwas, chairman of radical group the Indonesian Council of Mujahideen.
Anger has been growing at the decision to stage the Miss World beauty pageant in the world's most populous Muslim-majority nation.
A decision by organisers to drop the famed bikini round this year has failed to appease hardliners, who have pledged to stage huge demonstrations when the final takes place outside Jakarta on September 28.
The country's top Muslim clerical body and even the religious affairs minister have expressed anger at the pageant, which opens Sunday in Bali.
While most Indonesians in the nation of 240 million people practise a moderate form of Islam, a vocal hardline fringe has succeeded in getting events cancelled in the past.
Last year, pop sensation Lady Gaga axed a concert after hardliners threatened to burn down the venue and criticised her for wearing only "a bra and panties".