[Problem] Provided is a compound which has a PDE9-inhibiting action and is useful as an active ingredient for an agent for treating and/or preventing storage dysfunction, voiding dysfunction, and bladder/urethral diseases, and the like. [Means for Solution] The present inventors have investigated a compound which has a PDE9-inhibiting action and is useful as an active ingredient for an agent for treating and/or preventing storage dysfunction, voiding dysfunction, and bladder/urethral diseases, and the like, and thus, have found that an imidazoquinaxaline compound or a triazoloquinoxaline compound has a PDE9-inhibiting action, thereby completing the present invention. The imidazoquinoxaline compound or the triazoloquinoxaline compound of the present invention has a PDE9-inhibiting action and can be used as an agent for preventing and/or treating storage dysfunction, voiding dysfunction, and bladder/urethral diseases, and the like.
