Claire Blackman, wife of Sergeant Alexander Blackman, is "overjoyed" that her husband will be released from prison and returning home.
Mrs Blackman, who is from Taunton, has thanked those who have supported her through the campaign to free her husband, who was based with Plymouth's 42 Commando.
Sergeant Alexander Blackman, 42, known as Marine A, was originally sentenced to life for the murder of an injured Taliban fighter in Afghanistan.
But he will be freed from jail "within two weeks" after being re-sentenced to seven years.
It follows an appeal that claimed he was suffering from mental illness brought about by combat stress. Blackman was later charged with manslaughter, after his original murder conviction was downgraded.
South Dorset MP Richard Drax has worked tirelessly for justice for the former marine. He has welcomed the news that Blackman will be returning home, describing him as a hero.
The Ministry of Defence believes it to be "inappropriate" to comment on the court's decision.