Tongue color provides important information in traditional Chinese medicine (TCM) diagnosis, but in the process of TCM inspection, the various surrounding environment and subjective effect of doctors will influence the correctness of diagnosis. The present article put forward a brand new thought to study TCM objectivity, that is to research the essence message of tongue from perspective of spectrum, study the continuous spectrum to replace the observation of tongue color. The experiment used near infrared spectrum to collect reflection spectrum data of tongue among 53 exterior cold and interior heat patients, 37 healthy people and 21 wind chill suffers. Used matlab for data pretreatment, minitab for statistics modeling and prediction used partial least squares, the accuracy of prediction is 85.6%, but however, the spectrum of near infrared fail to distinguish exterior cold and interior heat patients from wind chill sufferers. The article provides a brand new way to implement the objectivity of tongue diagnosis in TCM, and also offers data support for the study of TCM syndrome.