34% of FDA approved drugs target G protein-coupled receptors (GPRCs). The dopamine D2 receptor (D2R) is currently targeted by all clinically used antipsychotic drugs. Understanding drug-binding kinetics and the underlying molecular mechanisms is important for the development of new ligands targeting the D2R. In the current project, antipsychotic drugs will be docked to crystal structures of the D2R (e.g., PDB: 6LUQ, 6CM4, 6VMS, and 7DFP), followed by molecular dynamics simulations to investigate the ligand-binding poses. Next, umbrella sampling will be used to evaluate the stability of the binding poses. The results may elucidate the crucial D2R residues that mediate antipsychotic binding. Additionally, the in silico findings may guide prospective experimental studies using point-mutated D2Rs.