Flatley is a native of the South Side of Chicago. He is of Irish American background, being born to Irish parents Michael and Eilish. His parents were both Irish-born, but migrated to the US several years before Michael's birth. Michael was the second of five children. He has three sisters, Anne-Marie, Eliza and Thomasina, as well as a brother Patrick.
He began dancing lessons at age 11 and at age 17 was the first American to secure a World Irish Dance title at the World Irish Dance Championships, the Oireachtas Rince na Cruinne. He is also an accomplished flautist, having won twice in the All-Ireland Fleadh Cheoil Concert Flute competitions from 1975-1976 and later in his career having released two albums. In his youth, Flatley also practiced amateur boxing; at age 17 he won the Chicago Golden Gloves Championship title.
Flatley was taught dance by Dennis Dennehy at the Dennehy School of Irish Dance in Chicago, then went on to produce his own show. After graduating from Brother Rice High School, on Chicago's Southwest Side, he opened a dance school, but later closed it down to focus on performing.
On the eve of the show's first full-length run in London, Flatley abruptly learned he had been replaced by the show producers due to conflicts over creative control. Just eleven days later after the split he created Warlords followed by Lord of the Dance, which played mostly in arenas and stadiums instead of stage theaters. He also put together a dance production called Feet of Flames in 1998. He later went on to produce another version of that show with around 50% different numbers from the 1998 show. Titled Feet of Flames: The Victory Tour, he toured Europe in 2000 and the U.S. in 2001.
Flatley broke his own record for tapping speed in February 1998, by achieving 35 taps per second. Flatley also received Guinness Book recognition in both 1999 and 2000 for being the highest paid dancer, earning $1,600,000 per week and for having the highest insurance policy placed on a dancer's legs at $40,000,000.
In December 2001, Flatley became the first recipient of the Irish Dancing Commission Fellowship award, an honorary degree in Irish dance, and was simultaneously made a Fellow of the American Irish Dance Teachers' Association. Irish America magazine named Flatley Irish American of the Year in March 2003. In 2004, Flatley received an honorary doctorate degree from University College Dublin, and that same year received the prestigious Ellis Island Medal of Honor in New York.
Flately's latest Irish dance show is Celtic Tiger, which opened in July 2005. The show explores the history of the Irish people and Irish emigration to the U.S., fusing a wide range of dance styles, including jazz. The show also includes popular elements from his previous shows, such as Flatley's flute solos and the line of dancers in the finale.
In 2006, Flatley released his own autobiographical book titled Lord of the Dance: My Story. Regarding his future, Flatley was quoted in the Celtic Tiger program book as saying, "I will be a dancer until the day I die".
In 2007, The Freedom of the City of Cork was conferred on Flatley at a ceremony in Cork's City Hall. In 2008, he was conferred with the Freedom of the Borough of Sligo at a ceremony in Sligo City Hall. The Variety Club of Ireland presented Flatley with their Entertainer of the Decade Award in 2008.
In fall 2007, Flatley and a troupe of male dancers performed on Dancing with the Stars in the U.S. In 2008, he appeared as a guest judge on an episode of the show, filling in for Len Goodman. Also in 2008, he performed the solo "Capone" from Celtic Tiger on the show. Flatley was also the host of the 2009 NBC series Superstars of Dance.
Flatley returned to the stage in 2009 for a limited run of the "Hyde Park" version of Feet of Flames in Taiwan. His return was met with multiple standing ovations and the run of shows had to be extended to meet the demand for tickets.
In 2010, he returned to headline the Lord of the Dance show, with performances in arenas across England and Ireland, Germany, Switzerland and Austria.Lord of the Dance 3D, the film of the return tour, debuted in theaters worldwide in 2011. The movie featured new sets, new costumes, state-of-the-art lighting, pyrotechnics and projections, and it shows the performances from the O2 Arenas of London, Dublin, and Berlin. A DVD and Blu-ray Disc of the film was released entitled Michael Flatley Returns as Lord of the Dance. The 3D version of the film was released only on Blu-ray.
Also in 2010, Flatley launched The Garden of Music and Memory in Culfadda, County Sligo, the village his father left to seek a new life in America. The ceremony included a speech and an impromptu performance of one of his father's favorite tunes. Flatley was also among the list of international film and sports stars and amateur golfers who participated in the fundraising golf Pro-Am, the JP McManus Pro-Am in Adare Manor Hotel and Golf Resort in Adare, County Limerick, Ireland in 2010.
On October 24, 2013, Flatley attended The Irish Post Awards on Park Lane where he received the Lifetime Achievement Award to recognise the impact of his career as a global dance superstar and entrepreneur.
In 1986, Flatley wed Polish make-up artist Beata Dziąba; they divorced in 1997.
In 2003, an allegation was made by real estate agent Tyna Marie Robertson that Flatley had raped her in 2002 at a Las Vegas hotel. In the subsequent court case she was ordered to pay $11 million compensation to Flatley for defamation and extortion.
In April 2006, Flatley spoke about his discovery of a facial skin cancer. He had kept the cancer a secret, but said, "I'm completely fine now, thank God."
On 15 November 2006 Flatley was admitted to a private London hospital with a viral infection. All the fall and winter tours of his latest production, Celtic Tiger, were cancelled. He was discharged two weeks later.
Niamh Flatley gave birth to a son, Michael St. James Flatley, on 26 April 2007.
Flatley's financial worth in 2006 was estimated at £350 million (US$530 million) in a Daily Mail article, and he is known to maintain homes in Barbados, United States, France, Ireland and London. As of 2010, his estimated fortune is around $650 million (UK: £421 million; Ireland: €495 million).