To provide a generated power predicting device easily predicting a wind velocity and a generated power after several hours at low cost in a wind power generator in a wind firm.

This device for predicting a power generated after several hours predicts the wind velocity after several hours by incorporating a recurrent neutral network (RNN) with a mechanism feeds back, as a context layer 3, a layer obtained by mapping an intermediate layer 2 with a time-lag of first order in addition to an input layer 1, an intermediate layer 2, and an output layer 4 and inputting the past meteorological data and the present meteorological data, and based on the information, predicts the generated power of a wind power generation plant.