The proposal came during a tour stop Friday in Tinley Park, Ill., outside Chicago. His representatives say he popped the question four songs into the concert after a Blackman drum solo.
She said yes, and they sealed it with a kiss, which was met with cheers from the crowd.
The multiplatinum-selling Grammy winner ended a 34-year marriage to Deborah Santana in 2007.
Blackman is a top drummer who has worked with the likes of Lenny Kravitz and Cassandra Wilson.
Santana says that he and Blackman are blessed to have found each other and says being in love "is a gift from the universe."