Ten-year-old Sajani, one of Nepal's top three kumaris, has been touring various cities abroad since last month to promote a documentary film about the Kumari of the Kathmandu Valley.
Her trip has made news in the US, but caused problems at home because kumaris are forbidden to leave Nepal.
Narendra Prasad Joshi, chief of the Bhaktapur Taleju temple, was quoted as saying temple officials had decided to replace Sajani as the kumari of Bhaktapur when she returns home later this week because, by travelling, she broke with tradition.
The kumari, worshipped by both Hindus and Buddhists, are selected between the ages of two and four after going through several tests.
During religious festivals the girls are wheeled around on a chariot pulled by devotees.
A kumari is required to have perfect skin, hair, eyes and teeth and the girls chosen usually keep the title until they start to menstruate.