A construction machine comprising: an electrical equipment installed in a vehicle body ; a communication terminal for transmitting information of the vehicle body to a server; and a battery for supplying power to the electrical equipment and the communication terminal , characterized in that : the construction machine further comprises: a plus-side main connection line for connecting the electrical equipment and a plus terminal of the battery ; a plus-side isolating switch provided on the plus-side main connection line for connecting or disconnecting the electrical equipment to or from the plus terminal of the battery ; a key switch positioned at a downstream side of the plus-side isolating switch and is connected in series to the plus-side isolating switch for connecting or disconnecting the electrical equipment to or from the plus terminal of the battery ; a plus-side auxiliary connection line positioned at an upstream side of the plus-side isolating switch for connecting the communication terminal and the plus terminal of the battery ; a minus-side main connection line for connecting a minus terminal of the battery to ground; and a minus-side isolating switch provided on the minus-side main connection line for connecting or disconnecting the minus terminal of the battery to or from the ground. an electrical equipment installed in a vehicle body ; a communication terminal for transmitting information of the vehicle body to a server; and a battery for supplying power to the electrical equipment and the communication terminal , characterized in that : the construction machine further comprises: a plus-side main connection line for connecting the electrical equipment and a plus terminal of the battery ; a plus-side isolating switch provided on the plus-side main connection line for connecting or disconnecting the electrical equipment to or from the plus terminal of the battery ; a key switch positioned at a downstream side of the plus-side isolating switch and is connected in series to the plus-side isolating switch for connecting or disconnecting the electrical equipment to or from the plus terminal of the battery ; a plus-side auxiliary connection line positioned at an upstream side of the plus-side isolating switch for connecting the communication terminal and the plus terminal of the battery ; a minus-side main connection line for connecting a minus terminal of the battery to ground; and a minus-side isolating switch provided on the minus-side main connection line for connecting or disconnecting the minus terminal of the battery to or from the ground. a plus-side main connection line for connecting the electrical equipment and a plus terminal of the battery ; a plus-side isolating switch provided on the plus-side main connection line for connecting or disconnecting the electrical equipment to or from the plus terminal of the battery ; a key switch positioned at a downstream side of the plus-side isolating switch and is connected in series to the plus-side isolating switch for connecting or disconnecting the electrical equipment to or from the plus terminal of the battery ; a plus-side auxiliary connection line positioned at an upstream side of the plus-side isolating switch for connecting the communication terminal and the plus terminal of the battery ; a minus-side main connection line for connecting a minus terminal of the battery to ground; and a minus-side isolating switch provided on the minus-side main connection line for connecting or disconnecting the minus terminal of the battery to or from the ground. <EOS>