BANGKOK — An 18-year-old Saudi runaway who feared death at the hands of her family if she were deported home from Thailand left for Canada on Friday, Thai officials said.

The Thai immigration chief, Surachate Hakparn, a police general, said Canada had granted asylum to the woman, Rahaf Mohammed Alqunun. His assertion was not immediately confirmed by Canadian officials.

She boarded a flight to Seoul late Friday evening and from there was scheduled to fly to Toronto, said General Surachate.

The events signaled a remarkable reversal in Ms. Alqunun’s fortunes from less than a week ago when she barricaded herself in a Bangkok airport hotel room to avoid being sent back.

“She’s lively, she’s smiling and healthy,” the general told reporters at a late-night airport news conference. “She said that as soon as she arrives in Canada, one of the first things she wants to do is learn the language. She has determination.”

She escaped from her family in Kuwait last Saturday and flew to Thailand. After being denied entry into the country, she rallied support on Twitter to avoid being deported, saying she feared her relatives might kill her if she were returned to them.

The 48-hour standoff at Suvarnabhumi Airport drew global attention through a social media campaign mounted by Ms. Alqunun from the hotel room, as well as by friends and supporters.

Ms. Alqunun’s original destination had been Australia, where she hoped to join other women who have fled Saudi Arabia, a patriarchal society where male family members can control even the smallest details of a woman’s life.

Both Canada and Australia interviewed Ms. Alqunun as part of the refugee placement process, she said. The final decision on where to send her was up to the United Nations refugee agency, which granted her refugee status earlier in the week.

But General Surachate said she preferred Canada over Australia for personal reasons.

“She wishes to go to Canada,” he said, “so we respect her wishes.”

Relations between Canada and Saudi Arabia have worsened in recent months after Canada called on the kingdom to release imprisoned rights activists. Saudi Arabia retaliated by expelling the Canadian ambassador, freezing new investment and trade deals and cutting other business ties.

Ms. Alqunun’s case received unusually quick consideration by the Thai authorities, the United Nations refugee agency, also known as UNHCR, and Canadian and Australian officials. Many asylum seekers wait years for placement in a country once they are accepted as refugees by the United Nations agency.

After Thai officials agreed on Monday to let Ms. Alqunun leave the airport, they were eager to have her case settled quickly so that she could depart for whatever country agreed to accept her.

Complicating matters, her father and brother arrived in Bangkok on Tuesday. In Saudi Arabia, women are not allowed to travel without a male guardian.

The father met with immigration and refugee agency officials to make the case that Ms. Alqunun should be returned to him. He argued that she needed medical treatment and should be under his family’s care. Ms. Alqunun refused to see them.

She said earlier in an interview that her brother had often beaten her, and that her family once locked her in a room for six months because she cut her hair in a way they didn’t like.

The immigration chief, General Surachate, met with the father, whom he declined to name but identified as a provincial governor in Saudi Arabia. He told reporters that Ms. Alqunun’s father had denied abusing her.

“Her father said that his daughter might have felt neglected because he has 10 children,” the immigration chief said. “Of course, it’s normal that parents worry about their child. But since the daughter asked to be under the care of UNHCR, we have to respect her request.”

Ms. Alqunun’s father and brother asked to see her before her departure but she refused to meet with them, the general said. They also were scheduled to leave Friday evening.

“This matter, therefore, ends for Thailand,” he said. “This issue is not about international relations. This is about a family affair.”

After she arrives in Canada, she will be under the care of the International Organization for Migration.

Thailand has moved more slowly in the case of Hakeem al-Araibi, a star soccer player from Bahrain who spoke out against a powerful official there and later fled the country. He was accepted as a refugee and granted asylum in Australia.

But in November, Mr. Araibi was arrested in Bangkok on a warrant from Bahrain when he arrived to go on his honeymoon. He has been detained since then and is fighting extradition to Bahrain. He fears that he would be tortured if he were returned.

Thailand has rejected calls from rights advocates and requests from the Australian government to free him. General Surachate has said Thailand cannot release him from detention because the arrest warrant has landed him in court, unlike Ms. Alqunun.

“She isn’t a suspect so she can travel anywhere in the world,” he said.

In a post on Twitter, Ms. Alqunun called for Mr. Araibi’s release and his return to Australia. Later, friends posted that Ms. Alqunun had closed her Twitter account because she was receiving death threats.