SNMP-based data collecting is fundamental for IP network management. This paper presents a SNMP-based Data Collect Algorithm for common use. According to requirement of data collecting, the algorithm disassem-bles collect tasks into metadata, and then reconstructs the protocol packet. Also takes full advantage of GetBulk op-eration, and brings out a combination algorithm for discrete variables of a MIB table so that the operation is opti-mized. A collect engine is implemented using the algorithm, which supports dynamic collection of multiple MIB vari-ables, supports arithmetic computing and logical computing, supports threshold judgment and sends out abnormalevents notifications. Tests are given to prove that the algorithm reduces the traffic for network management and im-proves the efficiency.