The hippocampus is important for contextual behavior, and the striatum plays key roles in decision making. When studying the functional relationships with the hippocampus, prior studies have focused mostly on the dorsolateral striatum (DLS), emphasizing the antagonistic relationships between the hippocampus and DLS in spatial versus response learning. By contrast, the functional relationships between the dorsomedial striatum (DMS) and hippocampus are relatively unknown. The current study reports that lesions to both the hippocampus and DMS profoundly impaired performance of rats in a visual scene-based memory task in which the animals were requiredto make a choice response by using visual scenes displayed inthe background. Analysis of simultaneous recordings of local field potentials revealed that the gamma oscillatory power was higher in the DMS, but not in CA1, when the rat performed the task using familiar scenesthan novel ones. In addition,the CA1-DMS networks increased coherence at, but not at , rhythm asthe rat masteredthe task. At the single-unit level, the neuronal populations in CA1 and DMS showed differential firing patterns when responses were made usingfamiliar visual scenesthan novel ones. Such learning-dependentfiring patterns were observed earlierinthe DMSthanin CA1 before the rat made choice responses. The present findings suggest that both the hippocampus and DMS process memory representations for visual scenes in parallel with different time courses and that flexible choice action using background visual scenes requires coordinated operations of the hippocampus and DMS at frequencies.