Abstract: A leaf spring inserted between a sealing member installed between various components of a gas turbine to prevent an inflow and outflow of gases and a mating sealing member, and a sealing assembly including the same are proposed. The leaf spring includes a curved body section, a locking protrusion protruding in one direction at an end of the body section so as to be fitted into the locking groove of the sealing member, and a detachment-prevention protrusion protruding in a direction opposite to the locking protrusion and configured to comes into contact with one surface of the mating sealing member and prevent the locking protrusion from being detached from the locking groove when the body section is compressed by the sealing member and the mating sealing member.