The Honey Bee hitmaker is said to have filed papers to end the union some time ago and an Oklahoma judge is expected to finalise the split on Monday (20Jul15), according to TMZ.com.
The estranged couple is allegedly sticking to the terms of its prenuptial agreement, which grants Shelton a ranch in Oklahoma, while Lambert will receive ownership of the pair's home in Nashville, Tennessee.
The stars, who wed in 2011, have yet to comment on the report.
It's Shelton's second failed marriage - he was previously married to Kaynette Gern for three years until 2006.
Huffington Post: Blake Shelton Miranda Lambert