The invention discloses an electromechanical transient modeling method for a distributed access type LCC-MMC hybrid direct current system. According to LCC-MMC hybrid direct current system components,an LCC rectification station electromechanical transient model, a direct current line electromechanical transient model, an MMC converter electromechanical transient model and an interface model between MMC converters are established. Therefore, the modeling method disclosed by the invention fills up the distributed access type LCC-; The blank of the electromechanical transient model of the MMC hybrid direct-current system avoids the adoption of an electromagnetic transient model for power grid planning and safe and stable calculation, so that the simulation speed and the calculation efficiency are improved, the response characteristic of the electromagnetic transient model can be effectively approached, and the calculation precision requirement is met.