The 15-time Grammy-winning singer tied the knot with music producer and rapper Swizz Beatz, real name Kasseem Dean, in 2010 and the pair have two sons, Egypt Daoud Ibarr, seven and three-year-old Genesis Ali.
On Tuesday, Keys, 37, shared a picture with her 13 million Instagram followers of her and Dean, 39, together.
Alongside the image, she wrote: “@therealswizzz Cheers to 8 year my love!!!! WOW! US! This LOVE!!! So amazing!! So infinite! So powerful! So electric!! It’s been the best 8 years of my LIFE!! I can only imagine the greatness the future holds!!
“Thank you for showing me what life is, what love is, what dreams are in infinite and endless awe and love!!!”
Dean also marked the anniversary, sharing a picture from the couple’s first wedding anniversary.
He captioned the picture: “This was our 1st Anniversary pic 8yrs ago today wow. I look crazy as hell but you look great as always #happyanniversary #8.”
US star Keys, whose hits include Fallin’, Empire State Of Mind and No One, has sold millions of records worldwide.