The switches installed in converter station valve halls in Xiangjiaba-Shanghai ±800 kV UHVDC project are expensive and maintenance inconvenience.Two optimization schemes of the valve hall grounding switches for researches on the function and operation of the switchers are presented.The two schemes are both studied in detail,with one way of abolishing all grounding switches on transformer valve side,and another way of partly cancelling the switches.Detailed analysis is further carried out for the feasibility and the pros and cons of the two schemes.Based on the comparison of two schemes,the partial reduction of grounding switches is selected to get a simulation with an EMTDC model.Plus in order to verify the reliability of the simulating results,a field test is carried out in Fengxian converter station with the partly switches cancellation scheme.The test results proved that using only one switch can still release residual charge in the valve hall in a relatively short period.Optimized designs of the valve hall switches can save both space and costs of the project.