A safety monitoring system (1) is provided with: a second sensor (30) for monitoring a second area; a first sensor (20) for monitoring a first area; a first processing unit (100) for detecting an approach of a human (6) to the second area; a second processing unit (200) for detecting an entry of the human into a dangerous area; and a mode determination unit (300). The mode determination unit determines a first mode when an approach of the human to the second area is not detected, and a second mode when an approach of the human to the second area is detected, and the operation differs between the first mode and the second mode.