We have developed a scheme to compute the standard potential of the Ag/AgCl reference electrode using density functional theory-based molecular dynamics, similar to the computational standard hydrogen electrode (SHE) developed by Cheng, Sulpizi, and Sprik [J. Chem. Phys. 2009, 131, 154504], with which our new computational reference electrode was compared. We have obtained a similar value of the potential of the Ag/AgCl electrode versus SHE to the experiment. The newly developed computational reference electrode will be extended to nonaqueous solvents in the future, where it will be used to predict standard equilibrium potentials to be compared with experimental data.