The incident occurred as the faithful jostled to reach a multilevel structure in Mina near Mecca to throw pebbles in a symbolic stoning of the devil.
TV footage showed the bodies of pilgrims, clad in white seamless pieces of cloth, lying on a road leading to the Jamarat building.
Nearly 2 million pilgrims participated in the symbolic stoning of the devil, a major ritual in the five-day annual haj pilgrimage, which started Tuesday.
Saudi authorities did not identify the nationalities of the victims.
In 2006, another haj stampede in Mina killed nearly 350 pilgrims.
The incident came three weeks after a construction crane collapsed in Mecca's Grand Mosque, Islam's holiest site, killing 107 people.
Muslims are expected to perform the pilgrimage, one of Islam's five pillars, at least once during their lifetimes if they have the means to do so.