Abstract:The applicability of thermometric titration method for the determination of sulfate in soil was studied.A thermistor was used to indicate the temperature change of the tat solution. A constant flow device was used to deliver the barium chloride solution as titrant. The titration curves were recorded automatically by a strip-chart recorder. It is found that the reproducibility of recovery of added sulfate was only about ±10% when thermometric titration method was directly applied to the determination in soil extracts. But in 50% alcohol solutions a reproducibility of about ±4% was obtained. The accuracy as compared with gravimetric method was about ±4%.The minimum content of sulfate which can be measurcd with:reasoaabl a accuracy is 1 meq/100g soil when proportion of soil to water is 1:5.It is concluded that the method has the advantage of rapidness with an accuracy comparable to indirect titration method by EDTA.