Racemic mixtures of mercaptosuccinic acid (MSA) are optically resolved to obtain enantiopure (R)-/(S)-MSA, and the (R)-/(S)-MSA-protected gold nanoclusters are synthesized. Circular dichroism responses of the nanoclusters are strongly dependent on the pH of the solution. In particular, chiroptical enhancement is observed under highly acidic conditions, which can be due both to the electronic and conformational origins of the surface chiral MSA ligand.