An Australian woman has been deported from Nepal for allegedly trying to convert people to Christianity.

Key points: 35-year-old was in country on a student visa

35-year-old was in country on a student visa But Nepalese officials say she was doorknocking to convince locals to join her religion

But Nepalese officials say she was doorknocking to convince locals to join her religion The woman was banned from returning to Nepal for five years

Sydney woman Katie Rachel Graham was arrested 20 days ago in the small town of Gularia, not far from the border with India.

The director of Nepal's Immigration Department, Bishnu Hari Upadhyay, told the ABC the 35-year-old was on a student visa, but was engaged in door-to-door evangelising.

"She breached our immigration act, engaged in conversions, which is strictly prohibited under our laws," he said.

"This is not first time she is visiting Nepal.

"Her first visit was in 2012 and since then she repeatedly came here."

Ms Graham was with four Nepalese locals who were also arrested for spreading Christianity.

District police said Bibles and pamphlets about Christianity were found with the group.

Evangelising against the law

Nepalese law prohibits proselytising and conversion.

Earlier this month, police arrested and deported two Japanese women for door-to-door evangelising.

Although Nepal declares itself to be a secular nation, Hinduism is the dominant religion and there is rising anti-Christian sentiment among hardline Hindus.

In May this year, four churches were destroyed by arson or fire-bombing.

Mr Upadhyay said immigration officials brought Ms Graham to Kathmandu before deporting her.

Ms Graham has been banned from entering Nepal for five years.

"She was kept in an immigration office here and allowed to go out with permission," Mr Upadhyay said.

"She was on study visa but she did wrong according to our law."