Are you asking about the Church of Jesus Christ of Latter-day
Saints or the Church of Jesus Christ?
The Church of Jesus Christ is another name for Christianity, and
was obviously founded by Jesus Christ. There may of course be
individual Christian churches with the name "The Church of Jesus
Christ", which were probably started by the pastors or
parishoners.
The Church of Jesus Christ of Latter-day Saints is a Christian
denomination, it is founded on the teachings of Jesus Christ but
was started by Joseph Smith.