Recently, because of wide utilization of renewable resources, in multi terminal direct current (MTDC) grids are considered. MTDC grids control is very important. Vector control method has been taken as the method of controlling MTDC grid, which includes inner current controllers (ICC) and outer controllers. Also, in this controlling method, outer controllers are composed of active power controllers and DC voltage as active channel and reactive power controllers and AC voltage as reactive channel. Voltage margin control method is used to control DC voltage. Also MTDC grids' controllers are optimized by using Honey-bee Mating Optimization Algorithm (HMBO) and the results are compared with classic regulation mode. In this paper, a DC four-terminal test grid has been used for evaluating performance of HBMO algorithm.