History and Objectives: Considering the role of triple vaccine in reduction of mortality as a result of three disastrous diseases diphtheria, tetanus and pertusis and its known side-effects and little information on the incidence of these complications in Kashan, this study was performed to determine the complications of triple vaccine in referrals of the health centers of Kashan in 1999.

Materials and Methods: The descriptive strategy of this study was carried out on 383 cases from 1.5 month to 6 years old. All of them were carefully examined by a pediatrician up to 48h for the occurrence of complications and the observed symptoms were collected in questionnaire and the data were analyzed.

Results: In this study, pain in the injection area, swelling, erythema, non-humorous behavior, fever, somnolence, loss of appetite, vomiting and crying were 44.7%, 31.4%, 27.7%, 37.8%, 54.5%, 9.4%, 16.2%, 7.5% and 5.3% in a total of 344 cases (89.9%).

Conclusion: The incidence rate of complications after injection of triple vaccine was rather high in Kashan and it is recommended to recognize the causative factors and its reduction.