AIM: To analyze factors affecting on adverse drug reactions (ADRs) in 122 cases, in order to avoid and reduce occurrence of ADRs. METHODS: The cases of ADRs by the pharmacist and the clinical reports were collected, and then counted up and analyzed. RESULTS: In 122 cases of ADRs, there were 11 severe cases, the others are ordinary. The most common clinical displays of ADRs were the lesion of skin and the append ants ( 50.82 %), followed by the lesion of digestive system ( 20.49 %) and nervous system responses ( 18.03 %). Anti-infective drugs showed the highest proportion of ADRs, accounting for 61.48% of the total. The affected patients ranged in age over 50 years ( 34.42 %) and low age ( 21.32 %). The most of ADRs were induced by IV drop ( 91.96 %). CONLUSION: For the child and the old man crowd clinical doctors must be prudent with the medicine, avoiding the unreasonable combination of the medications, use the anti-infective drugs reasonably and strengthen monitoring of its use, in order to reduce occurrence of ADRs.