Abstract: OBJECTIVE To develop the intelligent and accurate software of monitoring on drug use in order to decrease the harmfulness of preventable adverse drug events. METHODS To develop the “antibacterial-application software” successfully basing on pharmacokinetics and pharmacodynamics of antibiotics. To develop “the intelligent prescription screening system” successfully and realize the connection between “contraindications” with diagnosis of patients, their laboratory results basing on the information system of the hospital. Selected the respiratory medicine of a hospital as the experiment group, and the respiratory medicine of the other three hospitals as the contrast group. During the former 14 months, both groups were not intervened. During the latter 12 months, in the experimental group, using “the intelligent prescription screening system” and “antibacterial-application software” to examine prescriptions and returned the “contraindications” or antibacterial dose errors to the doctors and gave the relative education. There were no interventions in the contrast group. In addition, all adverse drug events of the two periods were surveyed. RESULTS In the experimental group, 38 serious preventable adverse drug events were discovered, the incidence was 2.7%. After intervention, medication errors and their percentage to prescriptions were from 89 and 1.43% the most to 27 and 0.36% the least. Thirteen serious preventable adverse drug events were found out, the incidence was 1.1%. The decline rate was evident. There was no change in the contrast group. CONCLUTION When prescriptions in which “contraindications” and antibacterial dose errors are present, they can be found out by the “system” and “antibacterial-application software”, and the incidence of preventable adverse drug events are able to be declined in the respiratory medicine.