An optical fiber sensing system according to this disclosure includes: a first optical fiber network (10A) configured to detect first sensing information about a monitoring target; a second optical fiber network (10B) configured to detect second sensing information about the monitoring target; a first reception unit (21A) configured to receive a first light signal from the first optical fiber network (10A); a second reception unit (21B) configured to receive a second light signal from the second optical fiber network (10B); and an identification unit (22) configured to identify the monitoring target, based on the first sensing information included in the first light signal, and the second sensing information included in the second light signal.