The blue light can successfully inactivate various Gram-positive bacteria (S. aureus, Staphylococcus epidermidis, Enterococcus faecalis, and Clostridium perfringens) and Gram-negative bacteria (A. baumannii, P. aeruginosa, Escherichia coli, Proteus vulgaris, and Klebsiella pneumonia) and is widely used for the clinical treatment of neonatal jaundice and acne. Recently researchers found that the blue light is also effective for the treatment of atopic dermatitis and psoriasis vulgaris. This paper reviews the literature published in recent years from home and abroad, introduces research progresses of the blue light in basic medicine and clinical medicine, and provides references for clinicians and scientific researchers.