Afridi has been sidelined since sustaining a ligament injury to his right knee during a test match in Sri Lanka in July, missing the Asia Cup and home series against England.
"Shaheen is now available for selection for the 17 and 19 October warm-up matches against England and Afghanistan, respectively during which his match fitness will be assessed by the team management," the PCB said in a statement.
Afridi, who has picked up 47 wickets in 40 T20s, is key to Pakistan's set-up, with his ability to bowl at high speeds and generate bounce likely to come in handy on Australian pitches.
"I am super excited ... it has been a difficult period for me to be miles away from the game and the team I love the most," said Afridi, who was named in the 15-man squad in the hope that he would be fit in time for the tournament.
"I have been bowling six to eight overs trouble-free for the past 10 days with full run-up and pace."
Reserve batsman Fakhar Zaman, who has been out with a knee injury, will also travel to Brisbane with Afridi.
Pakistan, T20 World Cup winners in 2009, open their campaign against India at the Melbourne Cricket Ground on October 23rd.
