It happened around 2:30am on Mystic Wood Drive near Woodsdale in northwest Harris County.
Two suspects reportedly ambushed the man while he was changing clothes inside his truck.
Deputies say the suspects had shotguns and demanded the man get out of the truck and hand them his keys.
He was giving them his keys when one the suspects decided to shoot him in the leg anyway, officials said.
The suspects got into the truck and drove off, leaving the victim bleeding on the pavement.
He called 911 and was rushed to an area hospital.
At last check, the victim was in stable condition at the hospital but the wound to his leg is so large doctors may have to amputate.