St Kilda forward Beau Maister has retired from AFL football, effective immediately.

After sustaining a season-ending shoulder injury in the VFL three weeks ago, Maister informed the club and his teammates of his decision earlier today.

The former West Coast player notched 21 games for St Kilda since being drafted in 2011, playing a total of 44 AFL games. He kicked 27 goals.

The 28-year-old will pursue business interests in his native Western Australia.

St Kilda Head of Football Chris Pelchen paid tribute to Maister for his time at the Saints.

"It is with real disappointment that we say goodbye to Beau as he has become one of the most admired and respected players within our group," Pelchen said.

"Since joining the Saints, he has performed to his absolute ability through sheer hard work and determination…qualities that have endeared him to everyone at the club.

"We thank Beau for his commitment to the Saints and wish him every success for the future."