To provide a hybrid type or battery type working machine which hardly gives a feeling of strangeness on an operation to an operator and in which electric power stored in a storage battery can be used effectively within an operation scheduled time set in advance. An amount of reduction in the amount of electricity stored in an electric storage device 60 in a predetermined time t1 after an working machine starts up is obtained, and an operation possible time t2 is obtained from the obtained amount of reduction and a residual amount of the electricity stored in the electric storage device 60. Further, determination is made as to whether the obtained operation possible time t2 reaches a remaining time of an operation scheduled time obtained by subtracting a currently spent real operation time from the operation schedule time set in advance. When determination is made that the operation possible time t2 does not reach the remaining time of the operation schedule time, a pump absorption horsepower maximum value is reduced to such a value that the operation possible time can reach the remaining time of the operation scheduled time.