Staff wearing "oni" demon masks tried to make the babies cry, with the first to bawl declared the winner by a sumo referee in an elaborate traditional uniform holding a wooden fan used to signal victory.
"We can tell a baby's health condition by listening to the way they cry. Today she may get nervous and not cry so much, but I want to hear her healthy crying," Hisae Watanabe, mother of an eight-month-old, told AFP.
The "crying sumo" is held at shrines and temples nationwide, to the delight of parents and onlookers.
Shigemi Fuji, chairman of Asakusa Tourism Federation which organised the event, said some people might think it's terrible they make babies cry.
"But in Japan, we believe babies who cry powerfully also grow up healthily. This
kind of event takes place in many places in Japan," he said.
A total of 64 babies participated in the ritual, according to the organiser.
The rules vary from region to region -- in some places parents want their offspring to be the first to cry, in others the first to weep is the loser.
