Mead won the role of Joseph through the BBC One programme 'Any Dream Will Do'.
The opening show was not without its glitches, however. In the middle of Tuesday's show, the West End performance had to be halted for 10 minutes due to a technical hitch when a revolving stage broke.
But Mead dismissed the mishap, saying: "That's theatre!"
Critics were largely won over by his performance, although some said his voice was not always strong enough.
According to The Telegraph's Charles Spencer, Mead "has a powerful and expressive voice" but added that "his vocals were beginning to sound a little frayed" by the end.
The audience at the Adelphi Theatre was packed with critics and celebrities, including Jason Donovan and Stephen Gately, who have previously played Joseph.
At the end of the performance, other contestants of the 'Any Dream Will Do' show joined Mead on stage, along with the musical's creators Sir Tim Rice and Andrew Lloyd Webber, following a standing ovation.
