Thorpe hails Root's 'work ethic' ahead of 100th Test
Root is set to reach the landmark when he leads England in the first of a four-match series against India in Chennai next week.
In the process he will become just the 15th Englishman in 144 years of Test cricket to have appeared in a hundred matches.
Fellow batsman Thorpe is one of the previous 14, having achieved the milestone in his final international outing, against Bangladesh in 2005.
"To play a hundred Test matches, it's no mean feat," Thorpe told a conference call on Friday. "His family will be very proud. He has always remained humble. He is a great student of the game.
"It is a real achievement because of the longevity of it," added Thorpe, who himself scored nearly 7,000 Test runs.
"You need a good sense of humour to play that amount of cricket because you will experience highs but there will some moments in there where you have your lows.
"You have to show a bit of character and resilience, you have to keep adapting and sometimes you will have to tinker with your technique and you have to manage all of that."
The now 51-year-old Thorpe, recalling his initial experience of watching Yorkshire batsman Root in action, added: "What I saw early on with Joe and I was fortunate enough to see some of his early games with Yorkshire, was character really. Character and temperament... He just had a great work ethic. He is always trying to get better."
Root heads into the India campaign in fine form following innings of 228 and 186 during England's 2-0 series clean sweep in Sri Lanka.
Those hundreds saw the 30-year-old climb into the top five of the Test batting rankings.
"The players who are in the team with him have a very good example to watch about how he goes about his business."