The invention discloses a method of using an electrochemical method to improve the performance of a REBCO high temperature superconducting thin film. The method comprises following steps: (a) preparing an organic solution; (b) using the prepared organic solution to process a REBCO high temperature superconducting thin film sample through an electrochemical method; and (c) after electrochemical treatment, taking out the REBCO high temperature superconducting thin film sample, and drying. The electrochemical method is used to increase the superconducting transition temperature and critical current density of the REBCO high temperature superconducting thin film. At the same time, the method is simple, is easy to perform, and is completely controllable.