The invention discloses a polybrominated diphenyl ether extracellular sensing protein and a whole-cell microbial sensor constructed by the polybrominated diphenyl ether extracellular sensing protein. The amino acid sequence of the polybrominated diphenyl ether extracellular sensing protein is as shown in SEQ ID NO. 3. According to the present invention, a polybrominated diphenyl ether recognition sensing protein is cloned from Sphingobium xenophagum C1, can specifically recognize polybrominated diphenyl ether, is fused with luciferase, is transferred into the Sphingobium xenophagum C1 with high cell surface hydrophobicity, and is subjected to overexpression of the fusion protein on the bacterial cell outer membrane to prepare the hydrophobic chassis whole-cell microbial sensor, the sensor has specific response to decabromodiphenyl ether and low-brominated homologs thereof, has obvious advantages in the aspect of monitoring hydrophobic organic pollutants, can remarkably improve the monitoring sensitivity of the hydrophobic organic pollutants, and has wide application prospects in organic pollution monitoring.