In　traditional　forestry　works,　the　compilation　of　volume　tables　by　cutting　down　trees　and　using　analytic　timber　volume　estimations　is　faced　of　problems　such　as　large　destruction,　high　costs　and　low　efficiency.　Therefore,　an　estimation　method　was　proposed.　First,　diameter　at　breast　height　and　ground　diameter　were　manually　measured.　Then,　the　horizontal　angles　and　zenith　distances　at　corresponding　trunk　positions　of　live　standing　trees　were　measured　by　using　the　approximate　division　of　analytic　timber　based　on　an　electronic　theodolite.　Finally,　the　timber　volume　was　estimated　by　simulating　mean　sectional　division　volume　as　per　summation　of　conical　frustum.　The　measured　data　of　standing　timber　volumes　from　poplar　in　Beijing　were　used　as　true　data　for　examination.　The　errors　of　timber　measurement　from　electronic　theodolites　were　theoretically　analyzed　according　to　error　propagation　laws.　Based　on　the　four　grades　of　electronic　theodolite　precision　classification　in　China:　I　(DJ1),　II　(DJ2),　III　(DJ6)　and　IV　(DJ15),　the　errors　and　the　limit　errors　of　root　mean　square　error　(RMSE)　during　measurements　of　tree　height　and　timber　volume　were　computed.　Moreover,　the　differences　and　applicability　of　electronic　theodolites　with　different　precision　levels　were　analyzed.　The　results　showed　that　because　of　error　propagation　and　accumulation,　the　errors　of　timber　volumes　measured　by　electronic　theodolites　with　the　same　precision　were　larger　than　the　errors　of　tree　height.　When　timbers　with　different　sizes　were　measured　by　electronic　theodolites　of　the　same　precision　level,　the　errors　slightly　changed　along　with　the　size　of　timbers.　With　the　increased　standard　deviation　in　angle　measurements　by　electronic　theodolites,　the　errors　in　forest　measurement　also　increased.　When　the　standard　deviation　of　electronic　theodolites　was　±0.5″,　the　RMSEs　in　measurements　of　tree　height　and　timber　volume　were　±6.550　0×10-2　m　and　±1.474×10-3　m3,　respectively,　while　the　relative　errors　were　0.44%　and　0.73%,　respectively.　When　the　standard　deviation　of　electronic　theodolites　was　±15.0″,　the　RMSEs　in　measurements　of　tree　height　and　timber　volume　were　±8.927　5×10-2　m　and　±4.385×10-3　m3,　respectively,　while　the　relative　errors　were　0.60%　and　2.14%,　respectively.　Therefore,　the　existing　I~IV　electronic　theodolites　applied　into　tree　measurements　all　conform　to　the　precision　requirement　that　relative　errors　do　not　exceed　3%~5%,　and　satisfy　the　requirements　of　different　forestry　works.　©,　2014,　Chinese　Society　of　Agricultural　Machinery.　All　right　reserved.