The major objective of this study is to investigate self- treatment with opium among the Hmong in a Hmong village of Petchaboon province. Twenty-four Hmong patients were observed and recorded for self-treatment behavior. The data were obtained through anthropological methods (observation, indepth interviews and group interviews) and through a standard survey. The period of this study was dusing the winter months in 1988. The results showed that the 24 Hmong patients under study had 50 illness episodes. One case died during the study period. The health seeking process began when the patient realined and abnormal symptom. Sickness was defined by the patients, and the same sickness could be described using several names or languages. The sickness comprised 5 groups : 1) diarrhea

2) pain and to have an ache in body

3) abnormalities due to an injury

4) abnormalities of the stomach

and 5) fever. Names of these sickness were learned from parents and social networks eccept some sickness treatable using Western medicine where the patients would name them base on physicians classification, e.g., "Kai-Vat and Malaria. The assesment of sickness was dependant on changes in the patients behavior, eatting, sleeping, walking, speaking and working. Rabits for unknown or uncertain illnesses patients would consult their social network, members in their family, "Klurlean" and lineage. These persons participated in the process of symptom definition and methods of treatment. Treatment regimes of the Hmong patients weere done step by step based on the degree of severity of illness. In case of Common and mild illness, the opium would be used for self-treatment among the current and temporary opium users. For non-opium users, howemver, self-treatment begins with taking the Nedicine bought from drugstore nearby. In case of severe illness or when self-treatment with opium or medicine fail to rid of the symptoms, both groups (opium users and non users) would go and seek help from either the private clinics or the district hospital. Opium is, therefor, used to treat common diseases such as cold and diarrhea of as a pain hiller in case of severe wonuded. Thongh using the opium is primarily bases on its medicinal value, when addicted to it, the negative cousequence of using it is quite evidence. These include the effects on social, economic and bealth of the opium users and their families. Attempt to improve the Hmong self-treatment should be in the form of health education which is based on the knowledge of Hmong culture, health regimes and the role of opium in Hmong society.