The present invention provides an acid resistant capsule shell composition comprising a water-soluble enteric polymer, a water-soluble film forming polymer, a coagulant, and a gelling aid. The water-soluble enteric polymer comprises hydrophobic functional groups and hydrophilic functional groups. The present invention further provides a process for preparing an acid resistant capsule shell comprising: dissolving said acid resistant capsule shell composition in deionized water to form a capsule shell solution heating then cooling the capsule shell solution to form a capsule shell stock solution dipping a pin into the capsule shell stock solution then removing the pin to form a film-coated pin and drying the film-coated pin to form the acid resistant capsule shell. The acid resistant capsule shell has acidic resistance and the process for preparing the acid resistant capsule shell is without organic solvent hence, the problem of organic solvent residues can be prevented.
