An active database mechanism is important to realize new information provision in current mobile and ubiquitous computing environments. Applying an active database mechanism to multidatabase environments realizes the automatic and meaningful information provision from various and heterogeneous databases. In this paper, we propose an aspect-oriented active rule system, called Aspect-ARM, for heterogeneous multimedia information resources. The Aspect-ARM provides an ECA rule language, called an aspect-ECA rule language, in adapting the rule system to the multimedia information in active and dynamic multidatabase environments. The aspect-ECA rule language is designed on a framework of conceptual data modeling for structuring complex multimedia data from multiple viewpoints. This model focuses on two concepts: "aspects" of multimedia data and "relationships" among multimedia data. We call this data model an aspect-oriented data model. The feature of this model is to deal with meanings included implicitly in media data in active rule evaluation. By introducing aspect-ECA rules with the aspect-oriented data model, it is possible to provide the active database functionality in cross-over multimedia database environments without affecting application structures and local information system structures.