With the increased utilization of EVLT, the negative experience, mistakes, potential hazards, and complications began to appear when using this method. The errors in the determination of any clinical parameter to predict complications give rise to other errors which, in their turn, lead to further errors. As a result, there is a group of complications that are almost impossible to predict in the individual patient. All complications of EVLT are logically divided into two groups: deterministic and stochastic ones. Deterministic complications are associated with the errors that are caused by violation of the EVLT procedures and are possible to avoid. These include laser fiber fragmentation, hyperpigmentation, skin burns, thrombophlebitis, and allergy to anesthetic. Laser fiber fragmentation at the site of manipulation is one of the most potentially dangerous event among the deterministic complications of EVLT. The more manipulations or devices are used during the surgical intervention, the higher the risk of development of such complications. Stochastic complications have no apparent cause. Stochastic complications include: deep vein thrombosis, pulmonary embolism, arteriovenous fistula, nerve injury, paresthesia, purulent complications, severe pain, and hematoma. In the group of stochastic complications of EVLT, the central place should be given to venous thrombosis and thromboembolism. According to different authors, the incidence of these conditions varies from 0 to 8%. The complications of EVLT can be divided into major and minor ones. No operation performed by the same surgeon can be repeated over and over again with exactly the same effectiveness and the number of complications.