A refrigerant cycle device having an ejector includes a first evaporator for evaporating refrigerant flowing out of the ejector, a first passage portion for guiding refrigerant to a refrigerant suction port of the ejector, a throttle unit located in the first passage portion, a second evaporator located in the first passage portion downstream of the throttle unit, a bypass passage portion for guiding hot gas refrigerant from a compressor into the second evaporator, a bypass opening and closing unit provided in the bypass passage portion. Furthermore, a second passage portion is branched from the bypass passage portion downstream of the bypass opening and closing unit, and a flow control unit is provided in the second passage portion to prevent a flow of refrigerant from the first evaporator to the second evaporator through the second passage portion. Therefore, defrosting of both the first and second evaporators can be suitably performed.