Steven M. Wilson of Kapaa was sentenced Wednesday to life in prison with the possibility of parole.
Wilson plead guilty in May to the 2013 stabbing and killing of his 21-year-old girlfriend Kendra Lewis.
Lewis was found dead at their home at the Kawaihau Sports Villa condominium.
Police say the two moved together to Kauai from Alaska in December 2012.
Kauai prosecutors are requesting a minimum 40 years before being eligible for parole.