An ideal molecular diagnostic method should be sensitive, specific, low cost, rapid, portable, and easy to operate. Traditional nucleic acid detection methods based mainly on PCR technology have not only high sensitivity and specificity, but also some limitations, such as the need for expensive equipment and skilled technicians, being both time and labor intensive, and difficult to implement in some regions. However, with the continuous development of CRISPR-Cas technology and its application in molecular diagnosis, new approaches have been used for the construction of molecular diagnostic systems. In this review, we discuss recent advances in CRISPR-based molecular diagnostic technologies and highlight the revolution they bring to the field of molecular diagnostics.