Posting on Instagram, the Hole singer shared a photo that showed her cuddling Cobain, prior to the singer taking his own life in April 1994.
“Happy birthday baby god I miss you”, she captioned the tribute.
One fan responded: “He is never forgotten and he will be loved forever. RIP Kurt. Happy 51st birthday legend.”
The emotional tribute comes after Love was forced to file official documents last year to prevent the publication of images from the scene of Cobain’s death.