The Corpus Christi Caller-Times reports Gonzales Ramos took the oath office Thursday afternoon, administered by U.S. District Judge John Rainey.
The U.S. Senate late Tuesday approved her nomination. President Barack Obama approved the confirmation Thursday morning.
Gonzales Ramos replaces U.S. District Judge Hayden Head, who went to senior status after announcing his retirement in 2009.
Gonzales, who's 45, is a Democrat and a native of Port Lavaca. She was a municipal court judge in Corpus Christi from 1997 to 1999, worked in private practice and has served as a state district judge since 2000.