He died from pneumonia at Stoke Mandeville Hospital in Buckinghamshire, his US agent Margo Lewis confirmed.This was a result of complications from a spinal cord injury sustained in 2003 which left him paralysed from the waist down, she added.
The Dave Clark Five had 19 UK Top 40 hits, including Bits and Pieces and the number one single Glad All Over. The group are due to be inducted into the US Rock and Roll Hall of Fame in New York on 10 March, alongside acts including Madonna, John Mellencamp and Leonard Cohen.
Ms Lewis said the singer and keyboardist was admitted to the hospital's intensive care unit on Wednesday with a chest infection.He had been in hospital since September 2003, but was released last December to live with his wife in a specially-prepared home nearby.
Ms Lewis said: "I am incredibly saddened to lose him, his energy and his humour."But I am comforted by the fact that he had the chance to spend his final months and days at home with his loving wife, Charlie, whom he adored, instead of in the hospital, and that he was able to attend a recent concert in London by his good friend, Bruce Springsteen."
She said Smith had felt honoured at the band's Hall of Fame induction."I am glad that he will be remembered as a 'Hall of Famer', because he was in so many ways," she added.
Rock and Roll Hall of Fame president Joel Peresman told Associated Press he was saddened by the news, but that the ceremony would go ahead as planned, with "a little extra significance".
The band, which broke up in the 1970s, sold more than 100 million records and recorded 23 albums, many of them for the US market.They were part of the so-called 1960s British invasion of the US, as the Beatles, Rolling Stones and The Animals stormed the American charts.
The Dave Clark Five had US hits with Because, I Like it Like That and Glad All Over, and set a record among British acts after appearing on the Ed Sullivan show 13 times.Bandmate Denis Payton, who played saxophone, harmonica and guitar, died of cancer in 2006.