Because　of　the　measuring　methods　for　deep　soil　parameters　(temperature　and　moisture)　are　offline　and　the　measurement　results　are　not　accurate,　and　meanwhile,　the　common　soil　sensors　can　not　be　used　for　the　real-time　measurement　of　deep　soil　in　geothermal　borehole.　In　this　paper,　we　design　a　temperature　and　moisture　sensor　and　a　data　processing　circuit　with　the　resistance　method　and　DS18B20,　and　develop　an　instrument　based　on　MSP430,　which　can　be　equipped　with　temperature　and　moisture　sensor　to　measure　the　soil＇s　parameters　at　different　depths　in　the　borehole.　Computer　can　get　real-time　status　information　of　instrument　and　control　the　instrument　from　PC　program　accurately,　which　can　achieve　the　requirements　of　real-time　measurement　of　the　temperature　and　moisture　under　different　soil　structures　and　layers.　©　2012　Chinese　Assoc　of　Automati.