Electroporation is a method to permeabilise cell membranes. It can be categorised as 1) reversible electroporation in order to increase the uptake of therapeutic molecules such as chemotherapy, calcium, or DNA, or 2) irreversible electroporation where the cell is permeabilised extensively, and both methods are used in cancer treatment. The treatment is brief and is performed under local or general anaesthesia. Electrochemotherapy and irreversible electroporation have proven efficient across different cancer histologies. This review describes the background for electroporation-based treatment, methods, and results of treatment.