With the development of laser technology, the applications of laser in the pulp diseases become more and more popular, especially in the treatment of root canals、pulp capping or pulpotomy, removal of filling materials or broken files, pulp analgesia and dental pulp devitalization. Laser as a means of adjuvant therapy can effectively improve the treatment result, and get a more stable prognosis in a long term. This article made a review on the effect of laser in the treatment of pulp diseases.