An in-pipe moving apparatus that can freely and smoothly move in a pipe having a bent portion and a branching portion, is not stuck in the pipe even if a drive motor of a movement mechanism fails or otherwise experiences a problem, and can be readily taken out of the pipe. The in-pipe moving apparatus includes two sets of wheel-based traveling elements (2A) and (2B), which each have two driving wheels (8A) and (8B) linearly arranged, and a variable bag, which is expanded and contracted in accordance with the pressure of a fluid supplied to the variable bag, and the two sets of wheel-based traveling elements (2A) and (2B) are so disposed as to sandwich the variable bag (3) and are fixed to the outer surface of the variable bag (3).