shortest man with irrefutable evidence was Gul Mohammed of India:22.5 inches tall. He Pingping was the shortest man able to walk according to Guinness World Records. He died on March 13th 2010 at the age of 21. He was 74 cm (2 feet 5 inches) tall.
...but it is rare. Shortest men * Gul Mohammed - Shortest man ever verified, measuring only 22.5 inches (57 cm), according to Guinness World Records. source: http://en.wikipedia.org/wiki/List_of_shortest_people
The shortest man alive is 26 inches (2 feet and 2 inches).The shortest man in history, deemed by Guinness, is Chandra Bahadur Dani. He was 72 years old in 2012 and measured 21.5 inches tall, taking the record from the former shortest man, who measured 22 inches tall.