Disclosed herein are a multicast apparatus and method. In the multicast method, a multicast apparatus searches one or more communication objects in a distributed network environment. Multicast data is received from a sender-side communication object among the one or more communication objects. A polling message is received from the communication object that transmitted the multicast data. A response message corresponding to the polling message is sent. It is determined whether a transmission error has occurred between communication objects based on results of sending of the response message, and multicasting is performed based on results of determination.