The 22-year-old injured his knee during the first Test against Sri Lanka in Galle in July and had to miss the Asian Cup (August-September) and the next seven-match T20I series against England.
The Pakistan Cricket Board (PCB) said Shaheen has completed his rehabilitation in the UK.
“Shaheen will join the men’s T20 World Cup national team at the ICC in Brisbane as per schedule on October 15, after undergoing a rehabilitation process,” a statement from the PCB read.
Pakistan has included Shaheen in the 15-man squad for the World Cup Fitness.
Pakistan plays two warm-up matches, the first against England on October 17 and against Afghanistan two days later, both in Brisbane.
The PCB said the left-arm meager slider will be available for warm-up games.
“I am extremely excited about the prospect of returning to the national team at the T20 World Cup and playing my part in our Australian campaign,” the statement quoted Shaheen as saying.
Top-tier hitter Fekhar Zaman is also on his way to recovering from a knee injury.
Zaman, who is one of three travel reserves for the T20 World Cup, will also travel to Brisbane with Shaheen and complete his qualification.
Pakistan has until October 15 to make any changes to its World Cup squad.
Pakistan is placed in Group B of the World Cup along with India, Bangladesh, South Africa and two qualifying teams.
They opened the tournament with a sell-out match against India in Melbourne on October 23.
Defending champions Australia, England, New Zealand, Afghanistan and two qualifying teams are placed in Group A.
The first round of the World Cup starts from 16 October.