Enteric coating substances were tested in terms of disintegration time of the preparations. The samples used are 8 brands of multiple digestive enzyme capsules containing enteric coated granules and 5 of enteric coated granules (2 anti-inflammatory enzyme preparations and 1 each preparation of an antipyretic, kallidinogenase and ATP). The dissolution test was also conducted on the digestive enzyme preparations. Although all the samples passed the disintegration test of J. P. IX, the disintegration time of all the samples delayed when pH of the test solution was less than 6.0. After detailed observation, the samples were classified into two groups: group 1 in which disintegration time delayed at 5.25 and stopped at pH 5.0, and group 2 in which the time delayed at pH 5.5 and stopped at pH 5.25. The delayings were also found in the dissolution profiles of active ingredients from the sample preparations. In the analysis of the enteric coating substances by infrared spectra, the substances in group 1 were identified with hydroxypropyl methyl cellulose phthalate and those in group 2 with cellulose acetate phthalate. It is concluded that enteric coating substances used in pharmaceutical preparations are identified by the disintegration time and infrared spectra.