The former first minister is a graduate from the institution, having studied mathematics with education, while also serving as president of the students' union, before going on to teach in local high schools.
He was appointed as Lord McConnell in 2015 and became vice-president for Unicef UK in 2015, now succeeding BBC journalist James Naughtie as the university's sixth chancellor.
Lord McConnell will preside over a further four ceremonies over the next two days after beginning his official duties on Tuesday.
He said: "The University of Stirling is a special place. The campus community, the innovative course design and assessment, and the commitment to wider access have given this place a permanent home in the hearts of those who have studied here.
"I feel truly honoured to return to the university to serve as chancellor, and I am looking forward to my first ceremonies this week when I can congratulate all graduates and honorary graduates on their achievements."
Double-Bafta award-winning director Hamish Hamilton was handed an honorary doctorate during the same event.
There are 2,113 students graduating at Stirling's three days of ceremonies, with honorary degrees for Outlander star Sam Heughan and French World Cup winner Lilian Thuram.
Professor Gerry McCormac, university principal and vice-chancellor, said: "Graduation is a time of special celebration - and this year's ceremonies are even more memorable.
"I warmly welcome home Jack - an alumnus of the university - to his new role and extend my congratulations to all of our graduands and honorary graduands on their hard-earned accomplishments."