The 27-year-old posted on Twitter on Saturday night that one supporter of the home team called him a “monkey”.
Austin grabbed the match ball, netting a hat-trick which kept the Fife side at the top of League Two.
He posted: “A perfect hat-trick tarnished by an Albion fan calling me a monkey but I guess that’s the world we live in enjoy your Saturday folks cos I will”.
An investigation is underway with both Kelty and Albion issuing statements condemning racist abuse.
"We are aware of an incident of racist abuse during our match against Albion Rovers FC” Kelty said in a statement.
"It came from an individual in the home end terracing towards one of our players. An investigation is underway with our friends from Albion Rovers, who gave all at our club a fantastic welcome on our first visit to Cliftonhill.
“Kelty Hearts Football Club shall support all of our players and members fully against racism of any kind, we strongly condemn racism and are totally committed to the elimination of all forms of discrimination.”
Manager Kevin Thomson added: “Stand by ALL of my players and staff!! @Fash_Austin94 no place for it ever, needs to change.”
Albion Rovers said: “We have been made aware of an incident during our Cinch SPFL League 2 match against Kelty Hearts. Albion Rovers fosters an inclusive area for all to take part in our beloved game without fear or prejudice.
“The Reigart stadium and wider Scottish football arena should be a safe place for all to enjoy the sport. We take seriously the allegations that have been made and condemn racism in all its forms.
“We will support the football authorities and law enforcement in bringing any perpetrators to justice.”
It is the latest incident involving alleged racial abuse in Scottish football
Airdrieonians star Rico Quitongo claimed on Tuesday that he was subjected to racial abuse by one of his own fans.
"Now as I’m not surprised with this still in football, I am more hugely disappointed to hear it from a section where my family would normally be sitting," he said.