A communication system for a working machine includes a communication device disposed on the working machine, and a mobile terminal to be connected to the communication device, the mobile terminal having a first application and a second application. The communication device has a first communication circuit to transmit, to the mobile terminal, a beacon including a first application identifier corresponding to the first application, and a second application identifier corresponding to the second application. And, the mobile terminal has a calculation circuit to execute the second application after the first application is activated.