Abstract: For further understanding simple Network Management Protocol, through the analysis of network management and SNMP, the authors point out the potential security problem of SNMP and the development trends of network management, describe the communication mode, component parts, communication protocol and management infomation base of SNMP, and list such menace to SNMP's security as role pretence, information modification, information divulgence, and denying of service, etc. The authors think that the core of SNMP has dangers in security because SMI (structure of management information) of SNMP is written by ASN. 1 (abstract syntax notation one) . At last, they analyze the development trends of network management, such as Web besed managemnent tools, DMTF(desk management task force), CORBA (cooperative object request broker architecture) and SNMPng (SNMP next generation), etc.