Vega allegedly shot and killed 20-year-old Morgan Sproles then dumped her body in southeast Houston earlier this week.
A passerby found the victim unresponsive, lying in the street. The victim had sustained an apparent gunshot wound.
Vega was arrested and charged after investigators identified him as a suspect.
Detectives did not say anything about their relationship or what led up to the murder.
She was pronounced dead at the scene.