It started around 5 p.m. at 609 SW 16th Street.
The man's wife had police escort her to her estranged husband's house to pack up her belongings.
Police told NewsWest 9 when the woman got to the home, her husband had a gun.
Police said they heard a gunshot and saw the woman running out of the house, screaming.
They got the woman to safety and set up a perimeter.
The Gaines County Sheriff's department and Texas Rangers from Midland came out to help.
They repeatedly tried to talk to the man and make contact with him but were unsuccessful.
Pepper spray was thrown into the home in order to get some movement out of the man but nothing happened.
"At that time I made a decision to go in, because I had a feeling that last shot was probably him and it was self inflicted. That's the angle were at right now. We're still early in the investigation," an official with Seminole PD, said.
The standoff was over by 7:45 p.m. Tuesday evening.
Police told NewsWest 9 at no time did the man ever fire at them and the wife was unharmed.
His identity has not been released, but KCBD, the NBC affiliate in Lubbock, told NewsWest 9 a neighbor informed them the man is Jay Brooks.