Social Network Service(SNS) have become very popular during the past few years. Also SNS, an current communication platform, greatly contributes to transmit the information rapidly and strengthen a sense of community and fellowship in military service. however it has vulnerable factors. For example, invasion of privacy, exposure of personal information and military data. In this particular case, it is a deathblow to the military service. Military Social Network Service require to protect the military security threats and disclosure of defense secrets. For such reasons we need the secure SNS that protects from any attacks or vulnerable factors. We present classification of functional type and analysis the SNS architecture. The goal of this work is propose military SNS security functional requirements for practical use safely.