In order to investigate the factors which determined the knowledge, attitude and practice of poliomyelitis vaccination, a study was conducted on 139 baby caretakers in Fefruary 1983. The data was analyzed with multivariate regression and correlation techniques, The absent rate, the proportion of population who do not live on the address they have registered, is rather high. In addition, the socioeconomic status of the population is generally low. Both of the factors resulted in a low vaccination rate. The vaccination knowledge of baby caretakers is highly correlated with their educational levels, socioeconomic status and the morbidity of poliomyelitis among neighbors. Vaccination rate is strongly correlated with the baby caretaker's educational status, cultural background of the family and the pat tern of seeking medical services in that paticular family. Results also indicated that people with higher socioeconomic status prefer to have a formal literal vaccination notification rather than a verbal, face to face communication which is required by those less privileged. The baby caretakers with poorer vaccination knowledge, lower socioeconomic status and older age prefer to be noticed each time of vaccination arid to be vaccinated at the front of their doors instead of going to health stations.