Hundreds of Buddhist villagers' homes were set ablaze and seven people were killed in rioting on Friday and Saturday.
State media says 17 people were injured and nearly 500 houses destroyed.
Police and military units were deployed to end the unrest.
A cycle of apparent revenge attacks began with rumours about the recent rape and murder of a Rakhine woman.
Three other towns have also been put under the curfew, which runs from 6pm to 6am.
State media said the situation was currently calm, but warned that groups of more than five people were banned, along with "giving speeches, marching and inciting unrest or any clashes".

'Anarchy' warnings

Rakhine state borders Bangladesh and is named for its dominant, mostly Buddhist ethnic group but is also home to a large Muslim population including the Rohingya, a stateless people described by the United Nations as one of the world's most persecuted minorities.
The Burmese government considers the Rohingya foreigners and not one of the nation's ethnic groups, while many citizens view them with hostility, believing they do not belong in the country.
The deadly sectarian violence between Buddhists and Muslims threatens to overshadow recent reforms.
Burma's state media has also warned of "anarchy", with the New Light of Myanmar newspaper urging people to exercise restraint in the wake of the rioting on Friday and Saturday.