Work machine and periphery monitoring system

A work machine comprising:

• a machine body;
• a front work device that is provided in the machine body;
• an operation device that outputs an operation signal for operating the machine body and the front work device on a basis of operation by an operator;
• and
• a sensor that detects an object around the machine body, wherein
• a controller that controls operations of the machine body and the front work device on a basis of the operation signal from the operation device, and performs operation limiting control for limiting the operation of at least one of the machine body and the front work device when the object is detected by the sensor, and
• an instruction device that instructs the controller to enable or disable the operation limiting control are included,
• the controller notifies the operator by a first state warning when the object is detected by the sensor and the operation limiting control is disabled by the instruction device, or when the operation device is operated in a state where the object is detected by the sensor and the operation limiting control is enabled by the instruction device, and
• the controller notifies the operator by a second state warning that is weaker in warning intensity than the first state warning when the operation device is not operated in a state where the object is detected by the sensor and the operation limiting control is enabled by the instruction device.