Safe and efficient oil sample collecting device

The invention discloses a safe and efficient oil sample collection device which comprises an oil extraction test tube. The oil extraction test tube is connected with one end of a sampling tube, and the other end of the sampling tube is simultaneously connected with a first tee junction and an oil discharge pipeline through a first connecting device; a first pressure sensor with an on-site displayfunction is mounted on the sampling pipe; the other end of the first tee junction is connected with an oil extraction pipeline, and a third end is connected with an oil return main pipeline; and a tail end of the oil discharging pipeline is connected with a piston cylinder which is provided with an inlet and an outlet, and a second stop valve is installed in front of the inlet of the piston cylinder. The oil sample collection device has functions and flows of oil circulation, residual oil utilization, oil sample collection and pipeline residual oil emptying. In the invention, an oil sample canbe always in a closed sta