Active rules and its processing mechanism have been the weaknesses in the research area of active database for a long time. The weaknesses were mainly represented: (1) The semantic of rules is not rich enough; (2) Lack of fundamental semantic; (3) Lack of hierarchical and structural description of rule processing. In this paper, in order to make up the above weakness, a rich extending semantic is given to the rule processing mechanism. A rule processing tree is represented to describe the influence of rule processing to the state of system structurally.and hierarchically.Based on the new system executing model and the extended transaction model,a rule processing algorithm the supports rich rule semantic can be represented.Comparing with othr similar algorithm,thealgorithm implements the new semantic.The using of recursive techursive technique makes the algorithm coincide with the rule processing.