Women and Child Welfare Minister Pramila Mallick entered the sanctum sanctorum of the Akhandalamani temple, a shrine of Lord Shiva at Aradi village in Bhadrak district, some 150 km from Bhubaneswar.
Temple chief priest Gokulananda Panda said they performed the purification ritual because Dalits were not allowed to enter the sanctum sanctorum.
The priests closed the temple for over an hour and washed it soon after the minister left, Panda said.
Mallik said she had visited the temple along with her family but didn't know if purification ritual was performed following her entry.
Dalits in Orissa are barred from entering many Hindu temples.
In November 2004, villagers beat up four Dalit women for entering an 18th century Jagannath temple at Keradagarh village in the coastal district of Kendrapada.