Abstract: A control system includes: a control valve control unit that controls a control valve; a data acquisition unit that acquires data on an operation command value and a cylinder speed in a state where an operation command for operating a hydraulic cylinder is output; and a deriving unit that derives operation characteristics in an operation direction of each of a plurality of hydraulic cylinders in relation to the operation command value based on the data acquired by the data acquisition unit. In acquisition of the data by the data acquisition unit, the control valve control unit controls a control valve of one pilot oil passage that is an acquisition object where the data is acquired among the plurality of pilot oil passages to open one pilot oil passage and controls control valves of the other pilot oil passages to close the other pilot oil passages.