A pipe coupling apparatus for simultaneously connecting and locking together pipe couplings comprising a plurality of sockets and plugs. The pipe coupling apparatus includes a socket-side unit having a plurality of sockets and a plug-side unit having a plurality of plugs. Each socket is provided with locking elements, and each plug is provided with an engagement groove. When the plug is inserted into the socket, the locking elements enter the engagement groove. A sleeve is provided displaceably between a locking completion position where it holds the locking elements from coming out of the engagement groove to lock the socket and the plug to each other and a retracted position separated from the locking completion position. A locking confirmation plate is displaceable from a locking unconfirmed position to a locking confirmed position when all the sleeves are at the locking completion position, thereby allowing confirmation of the completion of locking.