We have developed a self-healing key distribution scheme for secure multicast group communications for wireless sensor network environment. We present a strategy for securely distributing rekeying messages and specify techniques for joining and leaving a group. Access control in multicast system is usually achieved by encrypting the content using an encryption key, known as the group key (session key) that is only known by the group controller and all legitimate group members. In our scheme, all rekeying messages, except for unicast of an individual key, are transmitted without any encryption using one-way hash function and XOR operation. In our proposed scheme, nodes are capable of recovering lost session keys on their own, without requesting additional transmission from the group controller. The proposed scheme provides both backward and forward secrecy. We analyze the proposed scheme to verify that it satisfies the security and performance requirements for secure group communication.