The Dolphins defeated Hastings United 2-0 away from home in the third qualifying round of the prestigious domestic cup competition on Saturday.
Captain Jamie Whisken and Marvin Brooks were on target for the visitors at Pilot Field, as Poole made it through to the fourth and final qualifying round for the third time in 10 years.
Austin, who played for Poole during the 2008-09 season, was delighted with his former club’s progress in the FA Cup.
Congratulations @PooleTownFC delighted your through to the next round of the fa cup— Charlie Austin (@chazaustin9) October 10, 2015
Austin, who is injured at the moment, has been playing well for Championship side QPR this season.
The Englishman has scored seven goals and created 13 chances in nine league appearances for Rangers so far this campaign.
The 26-year-old has a pass accuracy of 64% and a shot accuracy of 48%, and has won 29 headers, five dribbles and nine tackles.