A steering rule provision method for traffic distribution in a network and a network entity performing the same network. A session management function (SMF) may transmit a first message including a multi-access rule (MAR) to a user plane function (UPF), when establishing or modifying a packet data unit (PDU) session for ATSSS (Access Traffic Steering, Switching, and Splitting). The SMF may receive a second message that is a response message to the first message from the UPF.