The goal of this research study is to identify the factorsthat influence demand for malaria clinics services and to developsuitable models to estimate the relationship between the demandfor the services and the factors influencing it. Malaria services in Thailand involve first and foremost,blood slides examinations of all patients attending the malariaclinics and then second, drug treatment of positive malariacases. Therefore, two models one, to estimate demand fortreatment services and other, to forecast the total demand forthe malaria services (measured by the total blood slidesexamination) are developed in this research. A priori theoretical considerations shows that the annualdemand for the malaria treatment services, Q, is a function ofservices (total annual blood slides examined), S, the annualhousehold income, I, mean travel distance X, the annual incidencerate, R and per capita government expenditure, G, spent annuallyon malaria control activities and expressed mathematically as Q = f(S, I, X, R, G) A pooled data from 10 sector malaria clinics of 3 districtsin Tak Province, Thailand for an average period of 3 years(1991-1993) are collected and fitted with the models developed.During the initial run of the regression, the variable R, isremoved from the function due to the problem ofmulticollinearity. R seems to have equal marginal effect as log Ion Q. However, the effect of lagged G on transmission rate andgametocyte output in the community indirectly explains the effectof R on Q and S. An error-components polling technique proves most efficientunder the present circumstances and it therefore forms the basisfor the development of the models after having accounted for thedistrict differences. The resulting function shows a significantpositive coefficient for variable S and negative coefficients forvariables I, X, and lagged G on the output variable Q. Also theother model developed to forecast S shows that to forecast S, oneonly requires the lagged values of S, I and G. The implications of these findings in planning and policyformulation are very revealing and important for managers in theservice. And most importantly the methods used in this researchcan be applied to develop a demand function in other areas inThailand and other countries.