A malware detection method for a home network system including one or more home appliances that are connected to a home network includes: obtaining a plurality of setting values including at least information indicating a device type and an operating state of a target device subject to malware detection; selecting one detection model out of a plurality of detection models according to the plurality of setting values obtained; obtaining power consumption or current consumption of the target device; and detecting whether the target device is infected with malware, using the one detection model selected in the selecting and based on the power consumption or the current consumption obtained.