Lazarev was born in Moscow on 1 April 1983. From ages six to nine Lazarev practiced artistic gymnastics. He began his acting and singing career before the age of 10, singing in the Lokteus Children Choir. At the age of 14, he had already received his first musical award, won several children’s song contests, and ended up as a member of child group Neposedi (Непоседы), the same group in which Yulia Volkova and Lena Katina of t.A.T.u. met each other. Also his friend Vlad Topalov (Влад Топалов) joined the band, who later would become the other half of Smash!!.

When he was eleven, he sang in the Pokrovsky Theatre, had parts in many plays. In 1995, at the age of 12, Lazarev entered the fidgets band, the same year he won the TV contest of children’s gold key. As a part of the fidgets group he took part in popular Russian TV programs and contests, such as Guess the Tune, Grasp Me, The Morning Star, Look Out, The Blue Light and the Slavonic Bazaar. In September 1996 Lazarev won the first prize at the contest Bravo Bravissimo in Italy. The same year he sang with the president orchestra led by Pavel B. Ovsyannikov.