The utility model relates to the technical field of thickened oil counting devices and discloses a thickened oil single-tank automatic counting device. The thickened oil single-tank automatic counting device comprises a thickened oil counting and separating device, an oil feeding pipeline, a gas pipeline, a liquid outlet pipeline, an oil discharging bypass pipeline, a gas flow meter, a dual-flange differential pressure transmitter, a gas discharging control electric ball valve, a liquid outlet control electric ball valve and a programmable control counting monitor, wherein the oil inlet pipeline, the gas pipeline at the upper portion of the thickened oil single-tank automatic counting device, and the liquid outlet pipeline at the lower end of the thickened oil single-tank automatic counting device are arranged on the thickened oil counting and separating device. The thickened oil single-tank automatic counting device is reasonable and compact in structure and convenient to use, the programmable control counting monitor controls the thickened oil inlet and outlet amount produced every time the thickened oil flows into a tank body, the liquid level increment and time consumed when the thickened oil flows into the tank body are measured through the dual-flange differential pressure transmitter, therefore, the daily oil production amount of each thickened oil well is calculated, and the counting error is small, through a single-rotating-rod pump, oil discharging time can be shortened, oil discharging efficiency is improved, continuousness of oil liquid counting is enhanced, and measurement efficiency is high, single-tank counting is adopted, and therefore the thickened oil single-tank automatic counting device is convenient to install and low in production cost.