Objectives : The purpose of this study is to introduce and examine the possibilities of infrared (IR) imaging, biophoton detection and gas discharge visualization(GDV) as diagnostic tools in Korean Medicine. Methods : To review the basic mechanism and measurement methods of three modalities, concepts in physics were introduced. Physical backgrounds of IR, biophoton and GDV were briefly explained based on recent research papers. Simple electronics was employed for relevant detectors. In order to find the relation between Korean Medicine and these methods, papers on their applications were reviewed. Opinions from the experts on each modality were obtained from their papers and private communications. Results and Conclusions : IR imaging has been used as an auxiliary diagnostic tool but there are some rooms for the improvement for clinical applications. Experimental confirmation of the meridian activation by a moxa cigar is necessary for its verification. Biophoton is not correlated with human skin temperature but it has a circadian rhythm. Biophoton and GDV have a negligible relation if any. Therefore there are no correlations among three modalities in terms of basic mechanisms. But their clinical relations are yet to be scrutinized. Biophoton and GDV need more rigorous clinical tests before they can be used as diagnostic tools.