In this study, we propose a method to design an optimal protection resistance value for preventing the accompanying short defects of high-parallel DRAM (dynamic random access memory) probe cards. The effect on the protection resistance in the low-frequency probe card RC circuit is verified. With the occurrence of a short defect in the probe card with 16 branches, the mathematical variation of the DUT (device under test) voltage and signal increases depending on the value of the protection resistance. Thus, the optimal protection resistance is selected. The transmission line characteristics are analyzed to derive the optimal protection resistance value of the probe card at high frequency. Finally, the probe card using the H-branch topology at high frequency extracts the optimal resistance value and acceptable range through simulation automation. Excellent signal integrity is verified for the circuit, which has an optimal protection resistance value, by comparing the area in the eye diagram.