Houston accidentally drowned in a hotel bathtub Feb. 11 after using cocaine. She was 48.
Houston and Brown were married from 1992 to 2007.
During their famously volatile relationship, both Houston and Brown battled addictions to drugs.
"Been about a month since you been gone. I guess it's pretty clear that you ain't coming home. Meanwhile, I'm trying to find the strength to move on, searching the streets, tryin' to find you a clone," Brown sings on "Don't Let Me Die."
The Guardian newspaper said the tribute to Houston will appear on "The Masterpiece," which is his first solo album in 14 years and due out next month.
"I didn't realize that every breath I took was from you. You were my air," he sings. "Don't let me die, girl."