The 27-year-old joined Villa's youth academy in the mid-1990s before penning his first professional deal in 2005.
Since then, Agbonlahor has gone on to score 79 goals in over 300 appearances for the club.
"I'm excited for this season and I'm excited for the next four years," he told Villa's official website. "It's a fantastic feeling for me to commit my future to Aston Villa. I can still remember my debut and the past 10 years have gone by crazy quick."
Agbonlahor and his Villa teammates return to action on Saturday when they travel to Liverpool in the Premier League.