To provide a controller for a showcase carrying out filter management using a filter sign sensor, and capable of preventing filter sign warning issuance due to filter clogging by providing a periodic cleaning guidance means, and prompting periodic cleaning of a filter.

The controller 110 for the showcase 100 is provided with a display output part 111, an operation control part 112, an warning output determining part 113, and a communication part 114. The warning output determining part 113 is provided with a periodic cleaning guidance warning output means 113a, and a periodic cleaning guidance warning signal is outputted to a warning device on the basis of a setting of the day of week or integrated hours (days) used as a periodic setting. The warning device carries out issuance of a warning sound, warning display, or the like in response to a periodic cleaning guidance warning or an output signal of another warning.