Vietnamese Huong and an Indonesian woman, Siti Aisyah, were charged with killing Kim Jong Nam by smearing his face with VX poison at Kuala Lumpur’s main airport in February 2017.
The two women claim they thought they were part of a reality TV prank which they had been rehearsing for weeks beforehand in various public places by smearing bystanders’ faces to see their reaction.
Huong had been wearing a t-shirt with the word LOL emblazoned across it when Kim Jong Nam was attacked and gained instant notoriety across Asia after CCTV footage was shown across the world.
Siti Aisyah was released last month after prosecutors dropped all charges against her.
Huong’s lawyer said she “had taken responsibility” for her actions by pleading guilty and after already serving two years in prison should be ready for release in May.
Four North Korean men escaped from Malaysia hours after the killing and are believed to be back in their homeland.
South Korean and American officials believe North Korea dictator Kim Jong Un ordered the assassination of his half brother, who had fled Pyongyang in 2011, after being a longstanding critic of the regime.
The North Korean government has denied the allegation.
Kim Jong Nam was living in exile in Macau before the killing and was carrying $100,000 in cash and four North Korean passports on the day he died.
The nerve agent which had been wiped on his face killed him within hours and he died in an ambulance on the way to hospital.
The 46-year-old had complained to airport staff that he felt dizzy and collapsed minutes later.
Judge Azmi Ariffin said Huong was “a very, very lucky person indeed”.
The Malaysian government had been petitioned by the Vietnam government and when the sentence was read out Vietnamese officials cheered.
Huong smiled and waved to her supporters as she left the courtroom.
She later told reporters after she would like to be an entertainer after she was freed.
She said: “I’m very happy. I want to sing and act.”
Speaking from her family home in the Red River Delta, Vietnam, Huong’s stepmother Nguyen Thi Vy said the family had worried about the death penalty.
She said: “No death penalty is good enough for now.”