Volatile organic compounds (VOC) in human exhaled breath reflects the health condition of body, which can be used for the assessment of disease. Diseaserelated exhaled biomarkers (e.g., acetone, nitric oxide, ammonia and ethanol) can be obtained by mass spectrometry. However, the source of most VOC is still unknown. Recently, the sensorbased exhaled breath analysis has made great progress. It is expected to achieve lowcost screening for early diagnosis and pathology of large population. The development of breath sensor has gained increasing interest. These studies are primarily concerned with specific sensors for the detection of individual compound. At present, the breath sensors include metal oxide sensors, carbon nanotube sensors, and colorimetric sensors. In addition, enose systems that consist of semiselective sensor array to simulate the mechanisms of smell sensing of human have been demonstrated in many medical applications. This article reviews and discusses the major mechanisms of different breath sensors and their recent applications in respiratory analysis.